heavy police presence at all hospitals. you should not read anything into that. are the eight scouring the area -- >> any thing unattended right now is being treated as a potential problem. we are methodically going through the area to check each particular parcel. >> we will be back with more information when we have it. background --me if you are a 20-year-old college student to grew up in boston, you'd be forgiven for thinking your mayor would forever be named menino. you can see the governor there who started his day by visiting the bear in the hospital. the mayor has had a number of health challenges, the longest

serving mayor in boston history. he has decided not to run for reelection, but you cannot keep him down on a daylight today. he got cleaned up and came over to greet the press. we did learn some new details. the police commissioner backing off reports that what ever ppened at the kennedy library was related to this call much less certain. a fire or incendiary device is a new story. library officials have said it was just an electrical fire. we have lost two sold in this today. 100 injuries, two confirmed dead at the finish line bombing of the boston marathon. just a time check -- 6:00 to eastern and we are told to expect the president in the briefing room at the white house under eight minutes from now. we will of course carry his

it's part of the grisly nature of the job of president, sending men and women into battle in getting the worst news first. we remember the president's remarks on the day of newtown and the president has a sad task today, with great widespread injury in boston. it usually the happiest day of the calendar in boston, the running of the boston marathon. the red sox played earlier today and instead, a virtually 15 block area in central boston is now locked down except public safety officials. it is now a crime scene. this was the first photo we saw this afternoon on social media indicating to us -- we got first

word of this of the atwitter that there had been a blast along the route of the marathon. then we saw the first photo showing a plume of smoke in the background and an orange flash. we later learned as we learned the grisly aftereffect, the reason we're talking about two fatalities, a mass casualty the foreground explosion is the second blast. or 20 secondst 15 apart. we have been talking to eyewitnesses' and our own correspondence. by our ownjoined national security analyst, former head of the counter- terrorism center for the federal government. since youn some time

and i spoke and enough time has elapsed. these were devices that were left there. were you content with the precautions and are you content based on what is in the public domain? that this is isolated to boston? get say't think i would things are isolated. i think that's the most likely outcome, but i think officials are taking excellent precautions and a number of cities around it populated areas to make se there are not things they don't yet understand. what everyone in the national security community will be scared of are the things they don't know and don't see and that's what the precautions are

for. we see a couple of things over the past several hours. first, the first reports are wrong. we have seen that be the case. there's a lot of confusion about whether there were other devices found. the answer is we are not sure. yorkials in boston, new and san francisco are increasing police presence and doing additional screening and that is exactly the right course. >> let's talk about something you don't hear much about that is important and germane. we have been at war for over a decade, brought to our doorstep on 9/11. this graduating class, if you forgive the flip expression, they have been forced to learn, and you are among them, so much about tactics, about the threat, about materials, at least that

kind of intellectual power is behind this and we are different when faced with it. we think about it differently than we did 15 years ago. >> that is absolutely right. with oklahoma city or even in 2001, the level of expertise, the debt of the counter- terrorism bench was a remarkably sen. people had much less background. today, we have established joint terrorism task forces, joining across the country and boston is a great example of that. that's a great strength we have. what we have to make sure is people don't fall into presuming this is the same approach they have seen in the past. that is the one caution i would

have. the depth of understanding about tactics, follow on threats, precautions are vastly improved since 9/11. we are still coming to grips with these developments and as he points out, first reports are wrong. it is axiomatic in law enforcement and the national security business. let's take a shot of the briefing room. we're going to keep a very close eye on the doorway. chuck taught is standing by. >> we just saw a notice being put on the podium, so maybe within the official window. we know that he has been getting a bunch of briefings since he may be initialled fell calls.

we also know the president has reached out to john boehner -- they just announced the two- minute warning -- the president spoke to the speaker of the house on the incident, presumably updating him about the information that he knows and is perhaps sharing with us. a lot of times in situations like this, he does come here with the official things that the government knows at this time. we expect it to not just be cut solar in chief, but helping us. >> allot of our stations would normally be in the middle of local news coverage or the afternoon talk shows that proceed local news. two different devices exploded. our working death toll, we have lost two people in boston, 100

injured. those are the last numbers. perhaps the president's remarks. we will update this. a 15-block area has been virtually shut down to all civilians, certainly all pedestrian traffic. for a time all transportation in and out of the city was stopped. so far, no reason to think a threat exists anywhere else but in boston this afternoon. earlier reports of a subsequent bombing at the john f. kennedy presidential library are being knocked down. but for now, we are in the midst of a huge and expanding investigation. next up, we hear from the president of the united states. >> good afternoon, everybody. bylier today, i was briefed my homeland security team about

the events in boston. we are continuing to monitor the response to the situation as it unfolds and i directed the full resources of the federal government to help state and local authorities to protect our people, increase security around the united states if necessary, and investigate what happened. the american people say a prayer for boston tonight and michelle and i send our thoughts and prayers to the families of the victims in the face of this senseless loss. we do not have all the answers, we know multiple people have been wounded, some of them gravely, at the boston marathon. i have spoken to the fbi director and secretary of homeland security and they are going to respond. i have talked to leaders in both parties and we have reaffirmed on a day like this there are no republicans and democrats, just

citizens concerned with our fellow citizens. i've spoken with the governor and mayor and made it sure is they know they have every single federal resources necessary to help the victims and counsel the families. i made clear to them that all people stand with the people of boston. boston police, firefighters and first responders and the national guard responded heroically. they continue to do so as we speak. it's a reminder so many service and sacrifice every day without regard to their own safety in dangerous and difficult circumstances. we salute all of those who responded so quickly to this tragedy. we still do not know who did this or why. people should not jump to conclusions before we have all the facts. but make no mistake, we will get to the bottom of this and we will find out who did this and why they did this.

responsible groups or individuals will feel the full weight of justice. today is a holiday in massachusetts, patriot's day. it's a day that celebrates the free and fiercely independent barrett that this great american city of boston has reflected from the earliest day of our nation. it draws people on the street in the spirit of friendly competition. boston is a tough and resilient town. so as a people, i am supremely confident bostonian will pull together and move forward as one proud city. as they do, the american people will be with them every single step of the way. you should anticipate as we get more information, our teams will provide you briefings. we are still in the investigation stage at this time, but we will find out who

did this and we will hold them accountable. thank you very much. >> chuck todd, directly in front of where the pay -- where the president was standing. we just heard this, repeating be added in the law enforcement that the first reports are wrong. the president cannot get out ahead of this and say too much too early. it's going to be a long night for investigators. >> for him to say we don't know who did this and not even a hint about whether this was domestic or international says a lot about what we don't know on this front. he made a point not to use the word terrorism for now. boston officials have used it and some folks on capitol hill have, and when somebody says why do you parse

certain words, certain words to matter. whoever did this, whether a person or group, we will deliver full justice. probably the most striking thing is how much information we don't know and how the president's went ahead and emphasize that. >> thank you. pete williams, our justice correspondent continues to work this story. but anything to add? the think it's safe to say concern about the possibility this could have been spreading around boston and they did not know where it was going next is starting to abate a little bit. it has not gone away because they still don't know who did this and that until they know that, they cannot know whoever is out there may not be plotting something like that again. it was useful to hear from the boston authorities knocking down some of the rumors out there that they had a suspect in

custody. they are questioning a number of people. there are police and federal agents talking to people, not only who were at the scene and were witnesses, but talking to people in hospitals with injuries. it is often times the case that people to set off bombs don't get away. the mere fact they are injured doesn't need their victims. they may have been involved that we know there are federal authorities and state authorities talking to people but nobody has been declared a suspect at this point. say we have safe to seen a lot of additional security being laid on by people who are watching this. airports are adding a security and you can be sure if there are rock concerts, any kind of

gatherings, there will be extra security at those places. whether they will change it substantially, that it probably cannot happen quickly, but we are told there is no directive urging authorities to do this. as the boston police commissioner said, no credible or specific intelligence of anything like this was applauded. i have not heard in the last couple of hours i have been using the phone that they have uncovered any intelligence that they have overlooked that suggest something like this was coming to boston or was planned for anywhere else. >> i'm not sure if any of this is good or bad. thank you. a quick word to our nbc stations. normally on the east coast, it is what is local news time and we would be using the air for a few minutes starting at 6:20 and

again if you are back on the east coast, we are back with nbc nightly news at 6:30. a lot of people involved in the marathon, it's not that many shades of separation between people in the marathon but a lot of folks know someone who is running and they would be curious to track them and make sure they are ok. wherehave some numbers people can go. mayor'st is the boston hot line. they can help you locate friends and families. the red cross has a web site and they say the patient. it is loading is slowly, but you can post that it is ok.

google has set up a people finder. or can't find someone there what people know you are ok. the other question we asked was about the supply of blood. they have sent a hundred units to the boston hospital but they believe they have enough blood on the shelf to handle the situation. runnersard all lot of got out of the race and wind up to donate blood, some of them have been experience with the explosion behind them. a quick follow-up. mayor's hotline, she read the correct number and we showed the wrong number. . 00 is the last four digits a 10 minute break in our live

coverage to allow our east coast television stations to get on and we will be back on the air for a special hour-long edition of nbc nightly news covering the twin bombings at the finish line of the boston marathon today. two people dead, 100 injured so far. we will be back on the air shortly. i'm brian williams in new york. >> this is breaking news. >> from baltimore, we continue to follow the explosions that occurred along the route of the boston marathon. people dead and at least 100 others being treated for various injuries. security has been tightened around the country. >> we continue our live team coverage live in baltimore with

a check on that part of the story. >> we have been saying all day this is a very difficult story to report on for a number of reasons. we typically try to answer the basic questions who, what, when, why, how? all we know is where and what time. we came to the university of maryland law school. it is professor michael greene murder's job to look at this and he analyzes the his mechanics. we thought he would be a good person to offer perspective as to what may have happened in boston today. categorize this as a terrorist attack.

>> no matter who did this, whether it's al qaeda or a u.s. citizen, this is a terror attack, a random, devastating act, perpetrated against innocent civilians. i have no doubt we will soon hear that someone who did this had some sort of grievance or cause. this is a classic terror attack, no matter who did it. when we first sat down with him tonight, it was unsettling because his first thoughts for wheat we were surprised we have not seen a terrorist attack like this in recent years. he said big cities like baltimore are always concerned about their stadium. so it can't in yards and a date drill constantly in and prepare for some areas like this and take steps to prevent some areas

like this. have a lot more about that at 11:00. the other thing that is quite hopeful is that since we have not seen an act like this, it is dodence the authorities will what they should be in. his final message was if you see something, say something. ofcould be a matter unintended baggage but if you say something, it could make a difference. >> thank you. the number for the maryland court nation and analysis center is 855-492-tips. >> the city plans to increase security for upcoming games and events, including tomorrow's orioles game. former chief the

of the maryland transportation authority, very much aware of what goes on. what is going on? baltimore city police department says they are in a state of heightened awareness. >> what people will see over the next few days will be an increased police presence as well as local law-enforcement coordinating with their partners of the state and federalevel. maryland is very fortunate to have a watch center. pushes information out to local law enforcement and local law-enforcement feeds the what centers so everyone is coordinating their efforts. >> what is what you are seeing so far suggest to you? >> it is still early. we are about four hours into this. it appears to be some act of domestic terrorism be.

the date is associated with this month of april, there is a lot of dates for whatever reasons who don't particularly care or the government. >> oklahoma city, waco -- >> with today being patriot's day in boston, and the significance attached to that day, it is tax day, so there are a lot of issues surrounding this day for certain individuals. >> there is also a very big event happening, the opening of the baltimore school of law. >> thank you. with over 400 runners from maryland, friends and relatives are working to locate the local runners in boston right now. >> in -- i know we talked a while ago and

you are still trying to get in touch with a lot of runners from howard county. >> manhattan we can actually get an update from the president of the court in sports entertainment and. maybe you can tell us here -- the question was, the latest from the howard county runners who are there. he any word yet? >> i have not been able to make contact for our anybody just yet. because of the cell phone issues? >> and i think they want to control the outflow of information. there's a lot of bad information out there and that the are trying to control it. >> the organizers of the baltimore marathon -- any changes you guys are going to make after an looking at what happened today? nice joba pretty

because of the baltimore police department. the office of emergency management does a great job. all of those cameras outside the stadium focusing on the parking lot, that gives us a great advantage and a great step up. >> thank you. >> the organizers of runners who took part in today's baldest -- in today's boston marathon. >> they are in touch with their people up in boston. he is sponsored a team of about 20 riders. what can you tell us about their conditions and were about? >> they are fine. most of them are younger and faster and most of them completed a course by the time that happened today.

what we have heard, they're fine. >> what do you think about this tragedy? >> it's horrible. there is the human element and then for my runners perspective, you devote a year or two years of your life and it's taken away by some senseless act that has nothing to do with the running community. she was of across the street from the explosion and said she it. they are ok tonight. >> thank you very much. you can see more pictures from the scene and the two blast caught on camera at wbaltv.com. >> to explosion that the finish

line of the boston marathon on patriots' day causing carnage and chaos. police have blocked down a 15- block radius near the finish line to sift through whatever evidence in an effort to track down the person or persons responsible. >> a horrifying afternoon for everyone today -- to people tend to be dead and at 100 people being treated at area hospitals. if you have seen the explosion video -- one of them really captures the horror of people screaming and running and seeking shelter. another group of people running to help. it was just a terrible scene this afternoon. >> we are fortunate that the 448 runners from the maryland area, most have been accounted for.

part, most runners from the maryland area have been accounted for. obamaheard from president say we will get to the bottom of this. thank you for joining us. at nbc nightly news with brian williams is next for an entire hour. breaking news tonight. an apparent coordinated attack in boston. a pair of home made bombs exploded at the finish line of a pair of home made bombs exploded at the finish line of the boston marathon. captions paid for by nbc-universal television good evening. yet again tonight we are coming on the air to announce another apparent act