wounded. certainly more than a. we have seen them coming out, men, women and children, with the kinds of lacerations that you would expect from this kind of an explosion. >> scott, one of the other problems is we are at the end of a marathon. they are dehydrated. they may be cold. it's hard enough to have an injury like this in normal conditions but if you have just run a marathon. >> pelley: we're being told that a third explosion occurred a short time ago, that it was intentionally set off by the police because they believed that they found an explosive device and decided to detonate it themselves before it went off. this is a report from our reporter kylie atwood who is

right there at the scene, and witnessed these events a little over an hour ago. kylie what do you know of that? >> yeah, hi, scott. i'm still standing at the medical tent on the corner of dartmouth and st. james. and it's still unsure what that third loud sound was. what we're hearing now is it could have been a potential bomb that was underneath the viewing bleachers that were right on boylston street near where the other two bombs went off. and because i'm being told now is that that material was detonated when the area was cleared. that can't be confirmed yet. but that's kind of what everyone is saying in this area right now. >> pelley: kylie, has anyone in authority there, any police officer, any fireman told you that they believed that these were actually explosive devices that were set often tensionally? >> no, no one has told me anything about what they know.

right now it seems that everyone is just trying to clear people out of here. as people are coming out of the medical tent one thing to note is that the people coming out now are sitting in wheelchairs and they may have their legs wrapped. but they're not profusely bleeding. we see wheelchairs that do have blood all over them. and those are from the victims that were directly affected by the bombs and were gotten out of here very quickly. so the people coming out of the tent now aren't as injured as the previous ones were. >> pelley: now kylie, you were there when the explosions occurred. once again, tell us what did that look like, sound like, tell us what you saw. >> yeah, scott, i was standing on boyle stoj street and i looked to my left and the first explosion went off. and we thought it was kind of a celebratory noise it was a huge, loud sound. but suddenly the air was filled with smoke. and you could sense that

something was gone wrong because everyone was running. i actually ran to my right and tripped on the ground because there were people going in all directions. and we actually ran towards where the second bomb went off. and we saw that go off. and tried to go in the other way, away from boylston street. and that's what everyone was doing. but as we were standing there and running, people were visually hurt there was blood on the ground. policeman were carrying children who had fallen. and the whole scene was really depressing to watch. >> pelley: this is videotape that you are watching that was shot about an hour ago of many of the victims being taken away from the scene of two explosions that struck near the finish line of the boston marathon.

many people have been woundedment we do not have any confirmed reports of death although witnesses say that they believe that some of the people that they saw had been killed. we do not have confirmation of that area hospitals had been told to prepare for mass cash uments and certainly we have seen quite a number of people heading to hospital its. we do not know the cause of the expo-- explosions but we do have videotape of both of the explosions that have come not newsroom this is the immediate aftermath. you can see people near the blast site lying on the sidewalk, near the finish line, conscious but clearly wounded. we also have videotape of the two explosions themselves. let me show that to you one more time. this is the smoke clearing from the first explosion as

the camera pans left you see its secretary explosion a block waya way. >> the boston police department is telling us now the two people have in fact been killed. and 22 people have been injured. in these twin explosions at the finish line of the boston marathon. this is official from the boston police department coming to us now two confirmed dead at this point. 22 wounded. those numbers will change as we learn more, of course. major garrett is at the white house for us today. and major, you're seeing some activity around there, even. >> yes, the security development we're sharing with you, scott. right now the secret service just to my right on the outside of the perimetre of the white house is beginning to cordon off pennsylvania avenue just north of this entrance to the white house. there is a considerable number of secret service vehicles moving into the

scene. pedestrians are not being allowed to approach the white house along pennsylvania avenue. on the southern side and now they're beginning to put yellow security tape near the southernmost part of lafayette scare. so there is a little bit of a security situation on pennsylvania avenue simply to limit pedestrian access to the closest part of the white house fence. that has something that we see with some regularity but it clearly in response to this event in boston. we reported earlier that there is some activity of this kind in new york going on. cities on the eastern seaboard appear to be sensitized highly to what is going on in boston and we're seeing some secret service activity just outside the northwest gate here at the white house. >> pelley: major, thank you. now these were relatively small explosions but they were in a very crowded space. this is the finish line of the boston marathon. thousands of runners. even more spectators. you can see them lining behind the blue fence there. you can see the spectators,

shoulder to shoulder, and very deep. many hundreds or thousands of spectators all along the 26 mile route. we're just getting these new pictures in now of the immediate aftermath of the explosions. we done know why they are saying this but the boston marathon officials are now describing the explosions as having been caused by bombs. this is not official from the police or the fire department but the boston marathon officials are describing the explosions as having been caused by bombs. we have videotape of the two explosions here is the first one, you see the smoke clearing, and about 10

seconds as the camera pans left will you see the secretary explosion which is about to my eye about a block away, and here it comes next. about 15 seconds, separates the two blasts, you can see the runners, still coming up boylston street to the finish line there as the explosions occur. we also have a very short clip that we're running on a loop that shows that first blast. here it comes again. watch for it. that is the first explosion. you see run of the runners goes down immediately. that is apparently the area where the largest number of casualties has occurred. boston police department is now telling us officially that two people have been killed, and 22 people wounded in these twin explosions at the boston marathon. >> you can imagine what the concussive force must have been for the gentleman to go down many feet from where the bomb went off and then

person went off in the middle of the street. that's one of the ways people get injured, whether they are hit by flying glass or shrapnel like material but just the concussion of it blows them away and it can cause brain trauma. >> bob orr is in our washington newsroom. bob what are you hearing? >> scott, as you pointed out the boston marathon folks are now labeling this twin bombs, the government will not go that far but i have to tell you that they were preceding down the belief that that is very likely what happened here. i mean what is influencing their thinking here is the coordinated or apparently coordinated nature of this. you have one explosion, that takes place, and then a short time later as you have been showing folks, in a fairly close distance a second explosion, that seems to indicate some level of orchestration, some level of planning and coordination. we want to be careful because there is no hard evidence at this point that these were deliberately

planted but if this were to be some kind of attack, domestic or foreign, among the things that those kinds of group was look for would be a high casualty count, a crowded area, it would be an extra plus to do it near an area where there is lots of security, ie the finish line and there would be more than one device. so those are the things when are you starting from 0 with very few facts you look at and you say hmmmm, we have to look hard to see if this was some kind of attack. on the other side of the ledger there could be another explanation less nefarious for this but as time goes on i think they are more easily able to rule out things like natural gas breaks and that kind of thing. the federal government is just now getting to a posture where it's getting experts into the scene. the fbi agents from the bureau of alcohol, tobacco, firearms and explosives. as you can imagine they were caught unaware from this there was security but there was not a triage and

forensic team in place, evidence collectors, if you will. now this is important also. if this is some kind of broad-based attack, and we're not saying it is. we're not even saying there are signs of that. but if there were to be a broader attack of-- we could look for problems other places. that's why you see major cities like new york and washington now moving to a somewhat higher level of preparedness. this, we are in the hours where the officials, state and local officials and federal officials really don't know what they are up against. we're going to air on the side of extreme caution. you'll see streets shut down, airspace closed. transit lines disrupted. there will be all kinds of temporary regulation in place. they will tighten this down across-the-board an not just in boss be to. until we get a cleaáe9 picture an at that point they can open the valves again and letting things gets back to normal. we're still in the early going here. i would repeat what i said a couple times, to this point.

there is no credible claim of responsibility. and there is nothing that i'm told in the threat pipeline before this event that signaled any kind of a potential targeting of the boston marathon. >> bob, thank you. threat pipeline, of course, meaning that there was nothing in the intelligence community, intelligence community hadn't picked up any kind of chatter or anything among known terrorist groups that might have suggested that something was coming. but what bob was describing as a sort of a national response, a terrorist response, we are already beginning to see some evidence of, major garrett at the white house, secret service, locking down the area around pennsylvania avenue, around the white house. and david martin at the pentagon is telling us that the military, the air force is sending aircraft to fly a combat air patrol, essentially, over the top of boston to make sure that there aren't any airspace

violations that are not authorized. and so we are beginning to see a reaction up and down the east coast here to this event. the boston marathon officials have told-- have said that those were bombs that struck near the finish line at about 2 is 10 this afternoon eastern time. the authorities have not made that official but nass's what the marathon people have told us. and in about 15 or 20 minutes, the boston police department fells us they're going to have a news conference to try to fill news on the details. what we do know from the boston police department at this point is that officially two people have been killed, at least 22 wounded, in two explosions that struck about 10 minutes after 2:00 near the finish line of the boston marathon.

that's the aftermath of the first explosion. you see the smoke clearing there. a blast on the sidewalk amid the crowd. now look down the road as the camera pans left, there is the second explosion about a block away. boston police, telling us two are dead, 22 wounded. we have seen quite a number of people taken away, bleeding, kind of trauma that you might expect from the shrapnel from an explosion. men, women and several children taken away. quite a number of people wounded in all of this. we have new videotape of an eye witness who was at the scene during the explosion. let's listen in to that for just a moment. >> there was some bad looking people. i'm praying for all of them. we are all trying to put pressure on the wounds for everybody, tourniquet, whatever we could do. it was chaos.

>> pelley: john lapook, clearly from the videotape and the witnesses bleeding is the thing that is causing so much trouble for these people. >> and the gentleman mentioned tourniquets, that is a classic way to stop bleeding. you take srx you tie it be, trying to make somethin something-- higher than the bleeding. >> pelley: it suggests arterial bleeding. >> and you can bleed out quickly from that, that is why it is so important to get first aid. >> pelley: we have an update on the number wounded. the boston police are telling us two dead and 23 wounded now. but of course those numbers will change as the information becomes more solid. on what is a terrible, terrible day at the boston marathon. that is the first explosion. the area behind that blue fence is jammed with spectators, behind all those flacks hundreds of people

watching the finish line of the boston marathon. you can see that runner right in the middle go down immediately from the concussive blast that occurred there. police and fire officials have not told us what caused these explosions. but we are beginning to see security tightened up in key areas along the east coast. the security has gone up even tighter than usual around the white house. david martin reports from the pentagon that the air force will be flying combat aircraft over boston to make sure that the airspace is clear the nypd in new york as it always does during a terrorist attack anywhere in the world has stepped up its security in the nation's largest city. and that is ongoing now

there is no indication that any other attack is eminent, if indeed this was an attack. we don't have any indication of that whatsoever at this point but security is going up in various places all around the country. the explosions happened a little after 2:00 eastern time, 2:10 at the finish line of the boston marathon of the first unexplosion and about 15 seconds later there was another. that is the smoke clearing from the first explosion and as the company ra plan pans to the left you see the second explosion down the street, about a block away. boston police are telling us two dead, 23 wounded. we've seen men, women and children being taken to ambulances, being taken away in wheelchairs and we are expecting a news conference from the boston news department later this

afternoon, they are saying 4:30 but these things have a tendency to slip. doctor you have been talking to people you know in the medical community there. what do we know. >> we know that 19 patients so far have been taken to mass general, massachusetts general hospital. now this is one of the great hospitals in the world with a terrific trauma center so they are in a terrific place. and i'm sure what they are doing now is just a session, making sure their vital signs are okay and their blood counts are okay. because there is the potential to lose a lot of bloods when you get these kind of injuries. >> but boston mass general, the other hospitals around. >> bringham. >> level one trauma centers, very best care available. >> the very best care available. i've been up there and visited these units and they are as good as anywhere in the world. >> major garrett at the white house for us has a little more information about what the president was told and when he was tomentd, majer? >> yeah, scott, the white house tells us the president was notified of the boston

situation about 3 p.m. this afternoon, and then he received a separate briefing from his new white house counterterrorism homeland security advisor, lisa monaco and other members of the senior staff that occurred in the oval office. after that the president called mayor menino of boston and the governor of the commonwealth of massachusetts, deval patrick offering his condolences for the victim and offering his full support of the federal government an all of its ways to deal with the situation both immediately and medium and long-term. >> major, thank you very much. >> if are you just joining us i would like to recap what we know at this point there were two explosions. near the finish line of the boston marathon p about 10 minutes of after 2:00. that's the first one, smoke clearing after the explosion. and then just about 10 more seconds will you see the second explosion as the camera pans to the left. it's down the block, about a block away. and there it is, the boston police are telling us that

they have confirmed two people have been killed. at least 23 have been injured. you can see some of the photographs that are coming it into the newsroom now of people being evacuated from the scene. these explosions were not large but they were in an incredibly crowded area. this was the finish line of the boston marathon where there were thousands of spectators, people standing shoulder to shoulder along that sidewalk where the explosions occurred. after the second explosion and in fact about half an hour ago, there was a third explosion but we were told by the boston police that this was a controlled explosion, that the police themselves set off on purpose because they believe that they had found a third explos oif device. this was told to one of our reporters, kylie atwood. and that they decided to detonate that device rather than let it go off, of course, on its own.

now that's one report but there was the sound of the third explosion about half an hour ago. and we're told that that was deliberately done by the boston police department to clear another device. there has not been any official confirmation that bombs caused these explosions. but the boston marathon officials are describing them as bombs. and we are expecting to hear from the boston police department in a news conference in 10 or 15 minutes time. bob orr has been talking to his sources in washington. bob, what do you know now? >> scott, i want to be careful here and take you through this very slowly so bear with me. but after the event, the government started looking at all intelligence sources and started to comb through every potential source of information. and so far at this point they do not see anything in the aftermath of the

explosions in boston that lead them to think that this was part of anything bigger. this is very important. they are not seeing any kind of chatter. they ever's not seeing any normal markers that you might expect if this were, say, an opening wave of something bigger. that doesn't mean that we can rule out that possibility. but it is encouraging at least at a minimum that right now this is starting to look, and i say starting to look like it might be focused solely on boston. we don't want too get too far down this road because there are so many unknowns. we know because we've seen the videotape and heard from the witnesses about the two explosions there are multiple reports of other possible devices at various locations around the boston area. we have to say that what is happening here is as the bomb squad start to check them out, they are disruptsing them. they are purposefully setsing them off this is what is done to neutralize any potential threat that doesn't mean these are real devices. it doesn't mean they are

actual bombs. it doesn't mean they would have gone off there may still be something else out there we don't know about. and in fact they are still responding right now to other calls. but this is the kind of thing that happens in the chaotic hours after an event like this. there are a lot of phone calls, tips, people see a lot of things and mistake no chances. right now as far as we know there were the two explosions we documented. we don't know if there were bombs or not. but i have to tell you that investigators are starting to look at that and say that is what it seems to be. that seems to be the most likely explanation because of the coordinated and sequential nature of that. but beyond that in looking at the threat matrix we don't see anything right now. i would emphasize we don't know everything here but we don't see anything right now that connects this to some kind of broader plot targeting other places. so that's at least good news for the moment in the federal government of course is still combing all sources. >> bob, thank you very much. we now have two sources that are telling us that at least one more explosive device

was discovered by the police and was destroyed. the associated press is reporting that two additional explosive devices were discovered by the police and were dealt with by the bomb squad. our reporter at the scene kylieiad woot-- atwood has told us she spoke with police officers who told her that one other device had been found and had been intentionally detonated by the police in order for it to be cleared. we have an eye witness to the event, steve silva who is on the telephone with us. steve, can you fell us what you saw? >> yeah, scott, i was down covering the finishes of the marathon. the folks coming in between 3 and 4 hours sit on the finish line with our cameramen and videographers. just runners straggling across the line on the perfect day and boom b 15 yards away from us the explosion went off on the corner of boylston and exeter street.

first we didn't know for a split second, was this something planned. then you could clearly see this was something off because the smoke spread and you heard the screams. we ran over there along with the police and rescue folks. and within 20 seconds we heard another explosion, another block up on boylsto boylston-- fairfield street at the same time. we knew something was serious. i got up close to the scene and it was a horrific scene, much like we see in the news in the middle east. i saw limbs severed. i knew there were going to be people dead in the case there was blood everywhere and just a chaotic scene. the police were trying to get in there, get everyone off the street because it was a crime scene. you had all the runners coming in it was full on panic. >> pelley: steve silva. steve, can you tell us a little bit abouted injured people that you saw. what were the nature of the injuries? what did you see? >> a lot of people with cuts and bruises there was an explosion at the marathon sports shop and the blast

blew-- the glass blew out you had facial cuts, limb cuts. i saw someone with a severed leg, immediately and it got worse from there. it was a horrific bloody scene, people strahled all over the sidewalk, blood all over the sidewalk. the police had to move the partitions back to get to the injured. the bulk of the medical people were in the tents streeting runners and they had to scramble and get up the street as fast as they could and get the ambulances in there. the streets were shut down. it was a difficult situation to street. >> pelley: steve silva, sports reporter covering the boston marathon. steve, thank you very much. boston police have now officially told thaws there are two dead. at least 23 wounded in two explosions at the boston marathon. this occurred about 2:10 eastern time. two explosions very near the finish line, right it finish line, another one it appeared about a block shy

of the finish line on boylston street in boston. we do not have official word that the explosions were caused by bombs but the boston marathon officials are describing them as bombs. we have received reports from our own reporter and also from the associated press that its police found at least one and maybe two additional explosive devices that the boston bomb squad has dealt with. bob orr has been talking to his sources and federal law enforcement. bob, what do you know? >> scott, we've been careful as we should be in something like this because we don't have anywhere close to all the facts here. and we laid out all the possibilities. these could be explosive devices, they could be something accidental. but when we asked federal official a short time ago are we safe in assuming that

these are bombs, he said, quote, heck yes, what else could they be. and he didn't say heck. so the presumption on behalf of federal investigators now is they are dealing with explosive devices that didn't accidentally end up there. but somebody obviously carried there. but again, that's just the first working theory. we have no idea if they were devices, what they were made of, or how large they were. we've seen the videotape and it's very hard to judge from the videotape but it seems to be consistent with a relatively small type of explosive that could be easily hidden in a trash canister, perhaps in a backpack. i mean this is a big public event. there's all kinds of security there. but in a crowd, in a huge crowd where people are carrying you know coolers and lunch boxes and backpacks, it is not a stretch and it's not hard to conceive how somebody if they wanted to do this could

carry something in quite harmful like a small explosive device. but again, the federal government, scott, is just getting its export-- experts there. they are calling in extra bomb squad resources to handle all the other calls they're getting. they're flooding the zone, so to speak, and hoping, really hoping that whatever is going on today is limited to today and just boston. other cities, of course, as we have note ready moving to a somewhat higher posture of security well. >> pelley: bob, thank you very much. dr. john lapook has been talking to his sources in the medical community in boston. you have some new information. >> right, dr. allister kuan says 19 patients, six critical, like a bomb explosion in baghdad. >> pelley: six in critical condition according to this physician, what hospital is that. >> at mass general. >> pelley: at >> at mass jeb. >> pelley: boston mass general. >> all right. 19 wounded at that hospital. >> correct. and that's so far. so we don't know what's still

closing up. >> pelley: i'd like to walk us through three imimagines that we have of these events that occurred about 2:10 eastern time. the first is a still photograph that we have of the actual explosion near the finish line of the boston marathon. you see e in the fore grown the runners running toward the finish line. that is the moment of one of these explosions in the crowd on the sidewalk right next to the finish line at the boston marathon. the next image i'd like to show you is a very short clip, a videotape that shows you the actual explosion. we have taken this tiny bit of videotape and there it is, we're running it in a loop so you can see what happens. behind that blue fence there are hundreds, probably thousands of spectators watching the finish line. you can see the blast takes one of the runners down, that man in

the middle of the frame falls immediately to the ground because of the concussive effects of that explosion. now, the third image i'd like to show you is of the two explosions. there is the one you just saw with the smoke clearing. this is the immediate aftermath of that. now in about ten more seconds the camera will pan to the left and there you see the smoke from the second explosion looks to be about a block away sources have told our reporters at the scene that police found at least one and maybe two other unexploded bombs and that the boston bomb squad has dealt with those. >> i have a little more information, scott. so far the injuries appear to be orthopeed nick nature but

they're doing x-rays and cat cat scans and m.r.i.s. most patients appear to be speculators. these were the spectators who were injured as opposed to the runners. and being in critical condition. all that means is you're intensive care unit. once you're there, the label is you're in critical condition so that really doesn't tell us too much about the nature of the injury. we'll have to wait to see what kind of reports we hear. >> pelley: we have eyewitness on the telephone, peg carter. peg, can you tell us what you saw? >> yes, we were standing between -- a little bit past the 26-mile mark when a big bang occurred. it was huge, there was smoke coming out and then a few second later, maybe ten seconds later i saw a big fireball shoot up, debris went out, smoke went out and i just grabbed my stuff and started running. so we just -- we just started running then we heard people --

everybody started running and screaming and somebody said that it was a bomb that went off so we were over here on comm ave. and they started sending people other here then we heard another explosion but i don't know if they set it off -- a third explosion but i don't know if that was set off by the police >> pelley: we believe the police detonated a third explosive device. can you tell us about what you saw in terms of the people who were wounded in this? >> i didn't -- it happened so fast i couldn't see. i knew there was a huge explosion in that people were hurt. i'm going to guess. but i didn't see actual people hurt and i grabbed my son and just started running.

>> pelley: peg carter, a witness to the boston marathon explosion this is afternoon. we're expecting a news conference from the boston police shortly but because of the chaotic nature of all of this we can't be sure when that's going to happen. this is just after 2:00 this afternoon. you see people pulling debris back from where one of these explosions occurred in the crowd at the finish line of the boston marathon. the boston police are telling us officially that two are dead, at least 23 are wounded. dr. jon lapook has found from his sources in boston that many of those patients are listed in critical condition. we have seen men, women, and children taken from the scene bleeding, broken bones, some people appear to have suffered amputations in these two explosions. a moment ago we walked you through the three images we have of these explosions.

i'd like to do that one more time so you can see what occurred just after 2:00. this is a still photograph. that's the explosion you see in the distance to orient you. this is boylston street. runners in the foreground are headed toward the finish line at 26.2 miles. that explosion has occurred on the sidewalk where there are hundreds of spectators lined up to cheer the runners on as they have finally made it to the finish line we have a very short piece of videotape that shows that explosion. here it is. we'll run it on a loop to you can see it. it's very short. behind that blue fence hundreds of spectators, that's where the dead and injured were. you can see that one of the runners in the middle of the road falls immediately down because of the concussive effects of that explosion. and then finally this last picture we have of the smoke

clearing from the first pass and ten seconds as the camera pans to the left you see the smoke from the second blast down the street about a block. there it is. that's the second explosion. bob orr has been talking to his sources in washington. bob, what do you know? >> scott, we're getting a bet better idea of how this went down. a law enforcement says that two devices that were exploded-- he called them bombs-- were likely located inside trash cans near the reviewing stand. we saw one picture and also in another location along the marathon route in addition to that, we are told by law enforcement sources that another device has been recovered intact and unexploded. if that turns out to be the case-- and we have this on good authority that they have this device this their hands-- this will be important forensically. it will tell them how the

devices were constructed. what they were made of. how powerful they were and could have clues that would lead them directly to the person who put that there. on the subject of potential suspects we have one law enforcement official-- and we want to be clear about what we know and what we're shaky on-- we have one law enforcement official who has told us there is a surveillance photo of someone described as a male, we believe, carrying what looked to be a couple of backpacks in the vicinity when these explosions took place prior to the explosions. that's important because if they have some kind of suspicion person on a surveillance loop, surveillance photo, the f.b.i., the police can circulate that there among all police agencies, perhaps among spectators how much they want to tip their hand i don't know and that could lead them somewhere. so these are big developments.

they're now willing to say outside they believe these were bombs. number two, they think they were probably secreted in some kind of trash can and that makes sense because after the explosions we heard about the warning to stay away from trash cans and very importantly the third device which we know about, an unexploded device we are told has been recover intact. that was in a trash resentable near the finish line. so these are preliminary bits of evidence, scott, but in the end it might help point us in the right direction. >> pelley: bob, thank you very much. so that would be our first law enforcement confirmation that explosive devices were behind these explosions in boston and apparently this attack was meant to be even graver than it has been. two bombs, apparently have exploded but at least one other has been discovered by police and, in fact, we're -- our

reporter is being told that there may have been two other explosive devices that were discovered and either dismantled or disarmed by the boston police bomb squad. to bring you up to date on what we know at this moment: about 2:10 near the finish line of the boston marathon, there were two explosions in the crowd. that is the aftermath of the first one and as this camera pans left in just about ten more seconds you will see the smoke rising from the second. there it is. smoke rising from the second bomb very closely coordinated. smoke rising about a block away. boston police are telling us that they have confirmed officially now that two are dead and at least 23 have been wounded. dr. jon lapook has been in touch with his sources in the boston medical community and he understands that at least nine

are in critical condition doctor, what kinds of wounds have people sufferd? >> they're mostly a *rt peed i can wounds but one witness talked about a severed limb. so anything from cuts and abrasions so something so serious it will need major surgery and when you have a severing of a limb it's not just the loss of that limb but the loss of the blood, a lot of arterial bleeding goes on. so one of the things these people will be doing in the intensive care unit and into the hospital is seeing what's their blood count, what's their blood pressure, how much resuscitation do they need. fortunately in a place like mass general and i hear there are some other hospitals involved we're talking about major world-class trauma centers and they've been trained to do this. i have to say, at columbia where i have we have drills where we go through all sorts of exercises to make sure we act very quickly. >> pelley: the best care available. john miller, our senior correspondent, former assistant director of the f.b.i., has been

talking to his sources. john, what are you hearing so far? >> it's a big scramble. they're trying to preserve two distinct crime scenes where they have post-blast investigations. that will be critical because they're going to find evidence of the bombs that did go off of course if what we're hearing is true-- and it sounds like reasonably good information that they discovered a device intact-- that gives them a big clue. this will be a long crime scene to process. when a device function it is way it's supposed to it breaks itself into a million pieces. they'll want to get every single one of those because it can literally be down to how the wire is twisted or what kind of timing devices is used that will give them the bombers' signature. all of that will go to the terrorist device exploitation center down at quantico and they'll go through that. that's the long game. the short game right now is one of great urgency.

you'll see the strategic information and operations center at the f.b.i. has filled up with people now. director mueller is in the command room there. he's in direct touch with the attorney general. and what they'll do now is put together a national and if necessary international coordinated investigation and go wherever they have to. boston p *d, of course, has the front lines here. their bomb squad is very busy. and the f.b.i. explosives section from quantico will be sending a big team of bomb technicians up to assist on that. not just the devices that went off but if they r *fr add device there, too. >> pelley: and the bureau of alcohol, tobacco, firearms and explosives would be involved in an explosive investigation as well. >> when you have a large post blast and a number of areas to cover the first thing you run short on is qualified bomb techs and a.t.f. is good at providing the people they have and the expertise they have also. >> pelley: we don't have any reason to believe that this is part of anything larger than an

attack on the boston marathon finish line. but we are seeing, as is standard procedure these days, a tightening of security in many places, especially here in the east. we have seen security tightened around the white house, david martin at the pentagon tells us that the pentagon is sending aircraft to cover boston we have been told by the new york police department that they have activated their plan for heightened security at all sensitive places after a terrorist attack. let me bring you up to date, please, on what we know at this point. at the finish line at the boston marathon at 2:10 khr-rp two

explosions. caught in this still photograph that place where you see the explosion occurring it was jammed with spectators. this is v.i.p. of that same explosion spectators behind that blue fence. boston police are telling us at least two are dead, 23 have been wounded, we understand a number of people have been wounded very seriously. there were two explosions that were timed apparently to follow each other very closely, that's the first one. smoke clearing from the first one. as the camera pans to the left and you look down the street about a block away you'll see the smoke. there it is, from the second explosion. about 15 seconds after the first explosion. we are told that at least one and maybe two other bombs were discovered by the police after these explosions and have been either dismantled, detonated or disarmed by the boston police department we have also on the

line one of our reporters withbz in boston. >> scott, it's paul burton here. i was actually running the boston marathon, finishing the race with a bunch of kids, about five of us. 50 yards from the explosion saw both of them go off. there was smoke and glass everywhere. and we did not know what it was at first. we thought -- it sounded like a cannon going off and we thought that was strange because we'd never heard cannons go off at any time during this race so we didn't know what to do. we kept on running and then when the second explosion happened we were stopped dead in our tracks and that's when everyone started running in the opposition direction towards us. we were literally about 50 yards from this finish line trying to finish this race and we saw it all unfold. i watched how the smoke and glass came across boylston street. my mother and my wife were in

the grand stands watching this. they were about 15 feet from the explosion. it was terrifying and obviously there were a lot of injuries in this and my heart goes out to the people who are injured and that apparently some people passed away. obviously my heart and prayers go with that family but it really -- we knew when we heard the second explosion that this race was over. >> pelley: paul burton of wbz. paul, thank you very much. jon lapook is getting new information from the hospitals involved. >> boston brigham and women's is now reporting unofficially that there are 18. this is from somebody i know there, not the official report. but that there are 18 wounded there. that's not official yet. >> pelley: our earlier report was that there were 19 at mass general. >> that's right. >> pelley: so a large number of people have been wounded in this. the boston police at this point are saying 23 injured, two dead. but these numbers were l change. >> pelley: i heard from one of my physician friends in boston, he said "i was walking through

the brigham and women's hospital coming back from a red sox game when they called code amber in the hospital. i said what's that? he said outside disaster, expect large number of patients." >> pelley: a disaster plan set up in advance by the hospitals in boston went into effect immediately after the first explosions as at least 30, 40 injured persons were taken away from the scene. the blast occurred right there where the large number of people had assembled to watch the race's finish the boston marathon on boylston street. two dead; 23 injured. we are waiting for the boston will police department to hold a news conference. we have our camera there and we will bring that to you the moment it begins but, of course, the boston police have their hands full now and a news

conference will happen when it happens. we are pecking it at any moment. here you're seeing many of the people being taken away from the site of the blast. many people cut. we're hearing that there are a lot of broken bones, as you might imagine. of at least some people apparently suffered traumatic amputation of their limbs near the blast site we've seen men, women, and children being removed from the area. this was immediately after the explosion that was closest to the finish line. you can see a number of people dazed but conscious, bleeding there at the finish line as people in this videotape are just trying to figure out what on earth had happened and get to the wounded which are covered in quite a bit of debris. the windows of that building in the background have been blasted out, of course.

the authorities are telling us that the explosions were bombs. bombs hidden in the crowd, watching the finish of the boston marathon. one bomb has been discovered and disarmed by the boston police. there have been as two that were found in the immediate aftermath of all of this. there's no reason to believe this is anything larger than an attack on the boston marathon but we are seeing a national security plan going into in effect various places, particularly here in the east. there is tighter security visibly around the white house. the new york police department has increased security throughout the city and david martin is telling us from the pentagon that the air force is sending aircraft -- will be sending aircraft toward boston to secure the airspace around there. bob orr has been talking to his sources in washington. bob? >> scott, i think at this point

what is not coming forward is helping investigators with their direction. what i mean by that is they've been looking at their intelligence channels, their threat reporting matrix prior to the event. they're also monitoring so-called chatter after the event. a couple things they're missing here: there was nothing in advance that suggested a threat aimed at this date or the boston marathon in particular there was nothing to indicate any kind of planning on the channels u.s. government officials monitor. and in the aftermath of what now appears to be twin bombings in boston, there is no chatter claiming responsibility. no chatter suggested this is connecting to something broader. >> pelley: the governor of massachusetts, de value patrick live. >> mindful of the fact that we don't have the whole picture yet but we have gotten a good deal of information. commissioner david will take all of us threw the information that

we have and i'll come back and talk about some of the ways in which we are going to ask people help us help you this afternoon. so let me turn it over now to ed davis, commissioner of police here in boston. >> thank you, governor. at 2:50 p.m. today there were simultaneous explosions that occurred along the route of the boston marathon near the finish line. these explosions occurred 50 to 100 yards apart and each scene resulted in multiple casualties. at this point in time, all of the victims have been removed from the scene. we have sent officers to hospitals to be in touch with family members and possible witnesses. we immediately ac activate add system of response that the commonwealth of massachusetts

and the federal government has in place for these type of incidents. my first two calls were to the special agent in charge of the f.b.i. and to the colonel of the state police, both rick deslauriers and tim albans immediately centre sources. we have at this point in time determined that there has been a third incident that has occurred. there was an explosion that occurred at the j.f.k. library. so this is very much an ongoing event at this point in time. we are not certain that these incidents are related but we are treating them as if they are. we're recommending to people that they stay home, that if they're in hotels in the area that they return to their rooms and that they don't go any place and congregate in large crowds. we want to make sure we completely stabilize this situation. we are setting up two telephone numbers that are very important. the first one is for families of

victims and people who are trying to locate people. that number is 617-635-4500. that is the mayor's hotline. the second number, if anyone saw anything at this incident, if anybody knows of any information that could lead to the arrest and the prosecution of the individuals responsible for this they should call us at 1-800-494-tips. that's 1-800-494 tips. that line will be staffed up tonight along with the f.b.i. and the state police we are working with the alcohol, tobacco, firearms and explosiv explosives, we have a general here from the massachusetts national guard who assiste assin securing the perimeter and we have additional assets from other agencies volunteering to assist us. after this incident occurred there were -- there was certainly a lot of people who were running from the scene some

of them deposited bags and parcels. each one is being treated as a suspicious device at this point in time. we have multiple teams checking these bags but at this point we have not found another device. the three incidents that occurred. two occurred simultaneously on boylston street and the third one occurred at j.f.k. about a half hour ago people should be calm but understand this is an ongoing event and understand we need all the information that we can get available to us. thank you. >> pelley: that's ed davis, the commissioner of police. this is governor patrick. >> about a half hour ago they assured us we would have full cooperation of the f.b.i. and the t a.t.f. who are also on the ground. we have the state police, the national guard fully deployed

and we thank them for their assistance. the fire marshal, the city fire marshal is here so a lot of coordination in a very fluid situation we are asking people stay out of crowds and calmly make their way home or if they're visiting back to their hotels. all of the hotels' security will be prioritized again. if people have information please use those tip lines. it's very, very important that we get as current information as we can as quickly as possible. happy to take any questions. >> reporter: (inaudible). >> well, you know, -- the marathon is a pretty special day around here, as you know, and i started this morning visiting

mayor menino in the hospital who was devastated that he couldn't be at the marathon today. he's on his way here now, i think. am i right, from the hospital so obviously he is as concerned as the rest of us are about the safety of the people who come for this iconic experience here in the city. >> reporter: can you address reports that you're looking for a specific kind of truck? >> no, there is no specific type of truck that we're looking for at this point in time. we are looking for any information that people have as to what they saw or might have heard at the site of the explosion or coming and going. we're investigating all leads right now. >> reporter: what is the latest death and injury toll? >> we don't have the number of casualties at this point in time. this is very early in the investigation. we wanted to give you as much information as we have but we can't tell you how many people were injured. >> reporter: there was a third explosion an hour ago and then

there was rumored that was a controlled explosion. do you know what that was? >> that was a controlled explosion on boylston street but there was an explosion at the j.f.k. library that we believe was related. >> reporter: (inaudible). >> as i explained earlier, there are a number of parcels that have been dropped by people on the parade route, on the race route. anything that's out there right now is being viewed as a suspicious device and we are clearing each one of those items with an e.o.d. team. they may be blowing things up over the course of the next few hours. but at this point in time we have not found another device on boylston street. >> reporter: had there been any warnings leading up to this that something like this might happen? >> none. we talk about the threat picture all the time as we lead up to this particular event and we have no information that this was going to happen. >> reporter: can you tell us what happens? >> it's literally just unfolding. i don't have specifics. there was an explosion there.

sorry? >> around 3:00 there was a fire. >> we got reports after 3:00 that there was an explosion. >> reporter: any injuries -- (inaudible). >> none that we know of. >> reporter: a would you say this was a terrorist attack? >> we're not being definitive on this right now. but you can reach your own conclusions based upon what happened. >> reporter: can you describe the diligence being paid to this. >> reporter: (inaudible). >> at this point in time, no. every asset of the commonwealth of massachusetts and the federal government is either here or coming here. as the governor said, the president has talked directly to the mayor as well as the governor and i had a personal conversation with the director of the f.b.i. who pledged any help that we needed so we are stabilizing the situation at this point in time but people should be cautious. that's all. thank you all very much. >> pelley: and so you've just been watching the news

conference live with the governor of massachusetts, deval patrick, and ed davis, the commissioner of police in boston. one of the things that we learned in that news conference was that there was a third bombing at roughly the same time at the john f. kennedy library in boston but a spokesman for the library says that there were no injuries there. so a third bombing at the j.f.k. library in boston but a spokesman for the library says no injuries there. there were apparently four bombs in all, two of them detonated near the finish line of the boston marathon, one detonated at the john f. kennedy library, a fourth device did not detonate, it was discovered by police and has been defused at this point in time. before the news conference boston police were telling us officially that there were two dead and 23 wounded but during the news conference you just heard they indicated that they did not have