let me get back to pierre thomas instead. pierre, from what you're talking to we just heard brad garrett and he's carefully calibrating what he said right now, but are you getting any indication from law enforcement officials right now that they have any idea who might have been behind this? >> again, too early according to my sources. they will have a list of the usual suspects that they will put on the table. but really the key is to try to get that information from the scene to point them in a particular direction. but until that happens, when they have a particular avenue to pursue. what they will look at is they'll go back over all intelligence, some of it which may have been deemed not credible, did they miss anything? they'll comb back through the previous intelligence leading up to today specifically anything that came into the boston area or the east coast. and they'll begin to look back. did we discount anything? did we blow anything away that we thought was not credible that we now know may be credible? that will be

we want to go to pierre thomas. what more have you learned, pierre? >> well, it struck me looking at that video, george, you can see the blast comes from a pretty contained area. and the chief let in some hints. he let in some hints into what they believe took plac he talks about the concern of packages about those left behind are being treated as packages. gives you a sense of what they believe caused these explosions. small portable devices that can be left in a crowd. >> what are you hearing about jfk library? >> we're trying to get additional information on that as well. i do have a federal source says two people believed to be dead, dozens injured. two people believed to be dead in this attack. >> we're starting to get reports from mayor bloomberg and los angeles police department as well going to take special precautions at the dodgers game tonight. we know pennsylvania avenue in front of the white house has been closed as well. what will police officers, police commissioners around the country be doing now in the wake of this bombing? >> here's

let me get back to pierre thomas instead. pierre, from what you're talking to we just heard brad garrett and he's carefully calibrating what he said right now, but are you getting any indication from law enforcement officials right now that they have any idea who might have been behind this? >> again, too early according to my sources. they will have a list of the usual suspects that they will put on the table. but really the key is to try to get that information from the scene to point them in a particular direction. but until that happens, when they have a particular avenue to pursue. what they will look at is they'll go back over all intelligence, some of it which may have been deemed not credible, did they miss anything? they'll comb back through the previous intelligence leading up to today specifically anything that came into the boston area or the east coast. and they'll begin to look back. did we discount anything? did we blow anything away that we thought was not credible that we now know may be credible? that will be

and pierre thomas joins us.

with the latest on the investigation here's abc's pierre thomas. >> reporter: is it dramatic videos likefic blast today that investigators will be combing through for clues of what happened this afternoon. two bombs exploding within seconds of each other and only 100 yards apart. the bombs were small portable devices that could have been carried in a backpack, easily concealed among the thousands of spectators and that's what makes this so difficult. >> it's not a lot of expertise. a small backpack sized bombs you can go on the internet and it will tell you the components and tell you about timers and using cell phones to detonate it as one device. authorities say there are no suspects but peter king saying there is a person at a local hospital who has come under scrutiny. >> i have heard there is someone in custody. he is being questioned and i guess the best way to describe it is a person of interest right now. >> reporter: hospitals reported seeing shrapnel wounds. >> a it will of small metal debris. some have asked if they were bbs or parts of bombs. i can't say whether it was placed

. >>> now we want to turn now to pierre thomas for more on the investigation. pierre, anything new at this hour? >> the information we have, there's a person at a local hospital up there in boston that they are talking to tonight. trying to get a sense of whether he's simply a witness or something more. that person's background is being checked as we speak. they're trying to get a mosaic of his life and determine whether he was involved or not. the other key thing going on, they're looking at the crime scene, trying to get pieces of those bombs, those two portable devices left at the scene to give them an indication of, is there a signature, a particular group or organization that uses these types of bombs? that will tell them a great deal. >> any sense, are they still going door to door, car to car along this 26-mile route? >> one of the things complicated the situation, a lot of people left their packages and pocket books and backpacks along the running route. so now, police have to go through each one of those items to see if there were any additional bombs l

i want to go now to pierre thomas, our chief justice correspondent in washington. pierre, i know the fbi special agent in charge is on the scene right now in watertown, but the top effort by the fbi in washington trying to identify these suspects. >> absolutely, george. the state officials and the boston officials who are giving the confirmation about suspect number one. the gentleman, the suspect with the black hat who has been killed and suspect number two, the gentleman with the white cap who they are seeking. i did speak with a senior fbi official who is expecting that they will give some additional information and updates later today. he said, it is clear that what happened yesterday by releasing those photographs and the video that they opened a bees hive, that these guys were run to ground by all the pressure being put on them. as brian just stated, the priority is getting suspect number two with the white hat. this official said this situation is extremely, extremely dangerous and they expect this person not to go doubt without a fight. >> as the commissione

pierre thomas, you're listening? >> reporter: diane, one of the things that struck me about the press conference is, it reminded us of the sheer violence we saw this week. the bombing. mangled people. the police chief tonight talked about 200 rounds being fired in the exchange with the suspects last night. bombs being thrown, homemade grenades. and he used a word that we don't often hear, we've been hearing too often of late, that the m.i.t. police officer was assassinated. i think we first reported today that they walked up on that security officer, that police officer, fired on him and executed him in his car. >> and, again, the police said they could detect his presence. the suspect's presence from those helicopters, presumably? >> they can do that. the extraordinary thing, and you mentioned it earlier, diane, that homeowner who went out there to check his boat and pulled back that tarp and saw that suspect there, it's incredible. incredible that that man is alive. >> and just reminding everyone that his friend an

with the latest on the investigation here's abc's pierre thomas. >> reporter: it is dramatic videos likehis and this, captured at the scene of the horrific blast today that investigators will be combing through for clues of what happened this afternoon. two bombs exploding within seconds of each other and only 100 yards apart. the bombs were small portable devices that could have been carried in a backpack, easily concealed among the thousands of spectators and that's what makes this investigation so difficult. >> doesn't take a lot of expertise to make small, handheld, backpack-sized bombs. you can go on the internet at this moment and it will tell you the components, it will tell you about timers, it will tell you about using cell phones to detonate it as one device. >> reporter: authorities say there are no suspects but peter king saying there is a person at a local hospital who has come under law enforcement scrutiny. >> i've heard several reports that there is a person who is in custody. he is being questioned and i guess the best way to describe it is a person of interest right now

we want to go to pierre thomas.n by the minute. >> reporter: the fbi and law enforcement officials say they're still hunting with the young man, we may be getting some additional information as brian ross reported. law enforcement officials have emphasized that this is probably the most tense situation they can recall in recent memory where the suspect is prepared to be confronted by law enforcement. you see an entire city, region, shut down. they don't want law enforcement doesn't want people out on the streets. also, as martha raddatz reported earlier, they're trying to find out everything they can about the young man's background and to make sure they don't have any associates. it's a very fluid situation. i just got off the phone with a senior fbi official saying they're waiting a an update. >> one of the chilling details police have told everyone in this lockdown situation not to come to the door, do not open the door unless you recognize the person standing there. want to go to byron pitts, he's there standing

. >>> now we want to turn now to pierre thomas for more on the investigation. pierre, anything new at this hour? >> the information we have, there's a person at a local hospital up there in boston that they are talking to tonight. trying to get a sense of whether he's simply a witness or something more. that person's background is being checked as we speak. they're trying to get a mosaic of his life and determine whether he was involved or not. the other key thing going on, they're looking at the crime scene, trying to get pieces of those bombs, those two portable devices left at the scene to give them an indication of, is there a signature, a particular group or organization that uses these types of bombs? that will tell them a great deal. >> any sense, are they still going door to door, car to car along this 26-mile route? >> one of the things complicated the situation, a lot of people left their packages and pocket books and backpacks along the running route. so now, police have to go through each one of those items to see if there were any additional bombs l

i think pierre thomas is back online. new information, pierre. >> reporter: george, we understand that the attorney general eric holder and fbi director robert mueller are about to brief the president shortly on the current situation, senior law enforcement official says no word that the second suspect is in custody. the situation still described as urgent, tense, grave, that the suspect is loaded for bear, expected to have a confrontation with police and possibly take hostages. >> let's go -- >> the president will be briefed shortly. >> back to brian ross on the scene in watertown. >> reporter: george, i wanted to add there's about an two-hour gap where it's not clear where they were after they robbed the car, got in the gunfight and then hijacked the car, robbed grocery store rather then got in th a high scombrjacked the car they were missing and it's presumed they went somewhere to stock up with more explosives which is how they loaded up that mercedes with so many devices anthe theory here at least an operating thryy a

pierre thomas reports. >> reporter: throughout texas fear and signs of tighter security. the kaufman county courthouse employees being walked in by armed guard. no prosecutions here, the district attorney's office is closed after the city's top prosecutor and his wife were murdered in cold blood saturday. they were shot multiple times with an assault rifle after an unknown gunman broke into their home. >> i would be less than honest if i told you i was not worried. >> reporter: kaufman district attorney mike mclelland's murder came only months after mike hasse was executed by two masked gunman. at the time, mclelland vowed his deputy's killer would be caught. >> we're going to find you. we're going to pull you out of whatever hole you're in. >> reporter: now mclelland has been murdered and prosecutors across the state are on alert some with 'round-the-clock police protection. >> obviously we're under attack. >> reporter: one prosecutor talked about warning from his wife when he left for work. >> she told me be careful. told me she loved me. i told her to be careful as wel

abc's pierre thomas has more. >> reporter: the deadly plot to derail a busy passenger train, en route from new york to toronto, murdering hundreds. >> had this plot been carried out, it would have resulted in innocent people being killed or seriously injured. >> reporter: the target, an amtrak passenger line that partners with canada's rail. thousands of people use the route from new york's penn station to toronto every year. sources tell abc news, the plan involved planting bombs to blow up tracks and derail the trains. >> we were looking at a real threat to kill people, hurt people. >> reporter: the two arrested suspects had allegedly begun surveillance of trains in the toronto area. but authorities had been watching them since august of last year. the plot was disrupted before it became operational. here's one of the suspects in handcuffs, escorted by police. and an unexpected twist. canadian authorities claim there's a link to al qaeda and iran. it's part of al qaeda's playbook. documents obtained from osama bin laden's secret compound revealed, he had been urging followers to der

i want to go to pierre thomas covering this all afternoon long from the justice department. there's some indication now there might be a person of interest in this case? >> yeah, i've spoken to federal authorities. there's a person that they apparently want to talk to, but this official was cautioning me, it mighting rou be routine proco get additional information. this is a person that has been identified that they want to talk to who's at the hospital. we don't know much more than that at this point. >> so they know where this person is, they know who this person is, they will be able to talk to this person? >> again, assuming that person is conscious, they will be able to talk to that person. again, my sources are reaching out to people in the boston area, near the hospital to try to get additional information, but no confirmation that this is a suspect at the moment. >> we're waiting for president obama now, expected to address the nation in about eight minutes. at 6:10 eastern time. abc news has been calling nearby hospitals, counting 86 patients in the hospital. take a

i want to bring in abc senior justice correspondent pierre thomas, who has been working this case on this easter sunday. and pierre, first, you had this assistant d.a. targeted, now the d.a. and his wife both murdered. they have got to be worried about some sort of bigger plan here. >> reporter: david, they really are. this is unprecedented. you have two men working in the same office, it was only weeks ago that the lead prosecutor was vowing to find out who killed one of his principle deputies. now, he's dead. so, law enforcement officials including the fbi, u.s. marshals and atf are down there, trying to assist police in this unfolding mystery. >> and of course, there's the other question about the prison chief in colorado who was also targeted and whether or not all three cases could be linked. >> reporter: well, they're looking at everything. no stone is going to be left unturned. in fact, you'll recall that there was a shootout a couple days after that prison chief was killed in texas. and they're now looking to see if there's any kind of link between these cases, because that pa

pierre thomas will keep working throughout the night, i know. and right after the explosion, pennsylvania avenue in front of the white house was shut down. shortly before we came on the air, the president addressed the nation. here's abc's chief white house correspondent jonathan karl. >> the president referred to the bombing as the event in boston, but make no mistake, the white house is treating this as a terrorist attack. when the president came into the briefing room a short while ago, he vowed to find out who was responsible and hold them responsible. we still do not know who did this or why. and people shouldn't 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, we'll find out why they did this. any responsible individuals, any responsible groups will feel the full weight of justice. >> the president said he's directed the full resources of the federal government to help not only with the investigation in boston and the recovery in boston, but also to

abc's senior justice correspondent, pierre thomas, with the latest. >> reporter: for years in littlen, texas, justice of the peace eric williams and his wife kim were known as solid citizens. and when district attorney mark mclelland and his wife were gunned down in their own home, williams expressed his sympathies. >> my heart goes out to all the families that have been affected by this tragedy. >> reporter: the case drew national attention and suspicion fell on white supremacist prison gangs. >> anything that the public can help with? >> not that we're releasing. >> reporter: but today authorities say the killers were none other than eric and kim williams. >> kim lene williams, 46, of kaufman, has been arrested and charged with the offense of capital murder. >> reporter: police say she confessed to her involvement in the murder scheme. according to court documents, she told investigators her husband shot to death the mclellands and also assistant district attorney mark hasse, gunned down near the courthouse in january. the alleged motive, revenge. mclelland and hasse prosecuted wil

pierre thomas, abc news, kaufman, texas. >>> and next we turn to north korea, the continuing threats of war today. the american secretary of defense called the threats, quote, a real and clear danger to the united states. tonight abc's chief global affairs correspondent martha raddatz is once again, in south korea, showing us how the united states is gearing up to respond if north korea is really intent on war. >> reporter: tonight, the u.s. says it stands poised to respond. >> some of the actions they've taken over the last few weeks present a real and clear danger. >> reporter: at the border, we were there with the troops on high alert. then, there is the missile battery being sent to guam, and the two guided missile sdroirs -- destroyers, eyes and ears scanning for the very first moves by the north. and warplanes, including fighter jets, u-2 spy planes and a-10 attack jets in the skies today, part of a massive military exercise overseen by a u.s. lieutenant general who brought in f-22 stealth fighters as well. they'd be first into the north if war broke out. >> their super cruise

abc's senior justice correspondent pierre thomas on how the sheriff says someone wanted him dead. >> reporter: arizona sheriff joe arpaio, whose tough illegal immigration stance has made him a controversial national figure, routinely receives treats. >> if i make some people angry, that's their problem. >> reporter: but tonight, he's dealing with a threat unlike any he's ever encountered. someone mailed arpaio what appears to be a bomb. >> it would have caused a major explosion and caused serious physical injury, burns and maybe death. >> reporter: the device was discovered by an alert postal worker who noticed a package addressed to arpaio with excessive postage. often a red flag for suspicious mail. it later started leaking powder. inside, a container of gunpowder attached to wires and batteries as a power source to detonate. the colorful and blunt arpaio was defiant, as usual. >> i will continue being the sheriff. i am not going to be intimidated by anyone. and that's a promise. that's a fact. >> reporter: with prosecutors recently killed in texas and a west virginia sheriff execu

we have pierre thomas. pierre, what did you learn? >> reporter: we have three federal law enforcement sources telling us that the suspect is in custody. condition unknown. condition unknown, diane, but our guidance is that the suspect is in custody. >> in custody. and again, it seemed inconceivable after all these reports of that gun fire and the way he was surrounded, pierre? >> reporter: again, we are unclear on what exactly his condition is, diane. i'm trying to get some clarity on that, but the guidance we have, a suspect is in custody and we should be getting further information from the boston and local authorities very soon. >> and again, we had heard that the hanneburys, saw the boat, saw blood in it, which indicated he might have been injured, maybe in serious condition in that boat, but brian ross, are you hearing the same thing? >> reporter: i am, diane. i just talked to with the state representative from this area. he confirmed that that was the suspect number two in the boat. that he, in fact, fired off a number of rounds

pierre thomas has been covering this all week. we appreciate your guidance this morning. >>> you were perhaps the first and the only reporter to talk with the boys' father. does he continue to believe his boys were framed? >> up until the last conversation, that is the case. he believes they are framed. the father lives in russia. he moved back a year ago. i spoke to him five times yesterday. he wept from angry to frightened to shocked. this is his angriest moment, when i asked him what he would say to his son. >>. [ speaking foreign language ] >> translator: if he's watching, i want to see him alive. i want to know the truth. what, when, why, where? this is a setup. i don't believe it. this is not possible. >> when he, you spoke to him later in the day, after -- you actually told him his son was captured alive. >> his tone changed to gratitude and relief. he said h russian, thank god. he said, i lost one son. i have one who survived. he said he'll be traveling to the u.s. soon to see his son, dzhokhar. >> let's turn to abc's mart

and pierre thomas is reporting what they want to see is how was it detonated, remotely detona detonatedll phone, right there, remote control. what did they use? how was it toed? that clue will probably lead them or at least hoping it will lead them to the person or group that did this. >> yes. coming up the unforgettable accounts from eyewitnesses. >> the fear in their voices and look in their eyes, after seeing something so unthinkable. >> later the 78-year-old marathon runner knocked down by the bomb impact. . unforgettable image, and his remarkable story. you're watching a special edition of "world news now." ay. >> good. you know, i'm really glad we got this insurance. dad taught me so much, especially how important it is to protect the ones you love. these policies will help do that if anything ever happens to either one of us. >> right, it was easy to apply for the coverage. >> it was. we answered a few simple health questions, didn't even have to take a physical, so we didn't miss any time from work. >> and it's affordable. it had to fit in to our budget, which isn't an easy thin

abc's senior justice correspondent pierre thomas following the investigation. >> reporter: it is dramatics and this, captured at the scene of the horrific blast that investigators will be combing through for clues of what happened. two bomb bombs exploding within seconds of each other and only 100 yards apart. the bombs were small, portable devices that could have been carried in a backpack, he's lis concealed among the thousands of spectators. that's what makes this investigation so difficult. authorities say there are no suspects, the bombs caused terrible injuries and hospitals reported seeing shrapnel wounds. >> there's a lot of small metal debris. some people have -- have asked already about whether these were bbs or parts of bombs. i just don't think we're able to say whether these were small bits of metal placed there intentionally or part of the environment. >> reporter: shrapnel is just one of the clues investigators will be looking at. >> there are fragments everywhere, there are fragments everywhere, there are fragments within the victims. fragments in the sidewalk. what they'r

abc's pierre thomas starts us off with the latest on that. pierre? >> authorities made clear the suspected terrorists had deadly intentions, and that such an attack could have been catastrophic. the deadly plot, to derail a busy passenger train en route from new york to toronto, murdering hundreds. >> had this plot been carried out, it would have resulted in innocent people being killed or seriously injured. >> reporter: the target, an amtrak passenger line that partners with canadian's via rail. thousands use the route from new york's penn station to toronto every year. the service crosses one of the most spectacular bridges in north america. sources tell abc news the plan was to plant bombs and derail the train. >> by derailing the train, we were looking at a real threat to kill people, hurt people. >> reporter: the two arrested suspects had allegedly begun surveillance of trains in the toronto area. but authorities

pierre thomas, abc new, washington. >>> the attack in boston getting attention on capitol hill.ubject of a full briefing for the senate intelligence committee last night. when it was over one republican said the attack might bring about changes in high profile events how those are are considered soft targets and how they're protected. >> this particular policy, the administration, and i am sure, and congress to evaluate overall security programs around the country particularly for major events. >> senator saxby chambliss suggested assistance may be offered to communities that host events that attract huge crowds. >>> as those injr.ed in the attack recover, they were getting helping hands from one man who saw it unfold. dr. david king is a trauma surgeon who saved lives in iraq and afghanistan. he had crossed the finish line not long before the bombs exploded. last night he told diane sawyer what he saw looked very much like a war zone. >> i was in the athlete recovery area for 30, 45 minutes. essentially had just left there. when the bomb went off. of course, immediately came to

pierre thomas, abc news, washington. >>> now to the boston bombing case.p in the long legal journey involving suspect dzhokhar tsarnaev. >> the 19-year-old charged with a federal crime, which brings the ultimate punishment. abc's marci gonzalez joining us this morning from boston with more. marci. >> reporter: good morning, john and diana. we learned at his bedside arraignment, the suspect said just one word. when asked if he could afford an attorney, he replied no. among the charges, 19-year-old suspect, dzhokhar tsarnaev faces one count of using a weapon of mass destruction. which carries a potential maximum sentence of death. we've learned despite the injury to his neck, he is cooperating with investigators, writing his answers to at least some of their questions. sources tell abc news, among the details he has provided is that he and his brother learned how to make bombs from the internet. >> it was his brother, the primary motivating force for him to become radicalized. why did they end up doing what they did on that day? >> reporter: much of the inve

marathon on monday and then, of course, the wild and violent overnight >> let's get more on this from pierre thomas in washington. pierre, as you've been reporting, brothers from chechnya, at least the two suspects we know of. >> reporter: that's the operating assumption right now, george, and just to piggyback on what briasan w saying, the situation right now, you're going to have that entire region under lockdown until they can find this second suspect. also there's concern that he might have associates, more bombs might be planted throughout the city. they are not taking any chancesl described this as the most serious situation as you can imagine. >> and, pierre, how quickly would they be able to figure out as we've been discussing the possibility that this second suspect has been in the united states for most of his life, for the last 12 years, how quickly would they be able to develop the information on whether he's gone back to chechnya or other places overseas for that paramilitary training you were discussing earlier? >> reporter: one of the things that's happening there is a massive vacuum

. >> we have pierre thomas looking into the situation.ndsay davis who is on the scene in watertown. can you hear us? >> reporter: i can. we are at the corner of mount auburn and kimball. it's a main street here that has just been shut down. police have set up a perimeter. we cannot get information on what is happening. we assume it's a search for the second suspect. it is members of the national guard and police here. maybe a dozen or so residents just standing on the streets trying to figure out what is going on. but a perimeter has been set. i don't know if you can see down there, several police cars are continuing to drive in and out of this area. that's pretty much what we can tell you at this point. >> it was a dangerous situation with reports of 30 gunshots and explosives being thrown out of a car during this chase. right now is there a sense of urgency where you're standing? do you get the feeling that whatever is taking place is taking place within a mile of where you're at? >> reporter: there is really no way to tell how close we

abc's senior justice correspondent pierre thomas on the race to make sure this doesn't happen again. >> reporter: today throughout texas, fear and signs of tighter security. the kaufman county courthouse, employees being walked in by armed guard. no prosecutions here today. the district attorney's office is closed after the city's top prosecutor and his wife were murdered in cold blood saturday. they were shot multiple times with an assault rifle after an unknown gunman broke into their home. >> i would be less than honest if i told you that i was not worried. >> reporter: kaufman district attorney mike mclelland's murder came only months after one of his top deputies, mark hasse, was

and abc's pierre thomas in washington has been tracking all the latest and has that right now for us. morning, pierre. >> reporter: good morning, josh. my sources tell me it's the evidence on scene and witnesses that will break open the case. the list of potential suspects could be long because investigators know this stretch of april is one with a dark history. this friday, april 19th, is also the anniversary of two of the most traumatic days in the country's recent history. in 1993, a 51-day standoff between federal law enforcement and branch davidian leader david koresh ended with 80 dead including 25 children when koresh refused to surrender peacefully. on the same day two years later, timothy mcveigh bombed the alfred murrah federal building in oklahoma city killing 168 including 19 children in the building's day care center. >> that attack was specifically designed as payback for the government's role in waco two years earlier. >> reporter: for those who hate america and know something of its history, monday had particular meaning. in massachusetts monday was a state holiday. pa

abc's senior justice correspondent pierre thomas has been on that angle all day. erre, good evening to you. >> good evening, dan. with the manhunt now over, the fbi is looking for a motive behind the bombings? was anyone else involved? where did they get that training? immigrants from the russian caucuses, the brothers came with their parents to the u.s. as children. seeking refugee status. they thrived attending top boston schools. older brother, tamerlan, 26, star athlete, golden glove boxer, pianist. younger brother dzhokhar, 19, had just become a u.s. citizen, ironically, on september 11th of last year. once a lifeguard, he was an all-state wrestler and college student. >> i certainly can't put it together that he was a person firing a weapon and potentially killing people. >> reporter: last night the fbi acknowledged it interviewed tamerlan in 2011 based on a tip from the russians. the russians said he was a radical islamist, preparing to leave the u.s., possibly for a trip to the caucuses. after looking into tamerlan's phone records, websites he visited and a

more on the suspects from pierre thomas. kely brothers and the way they engaged the police is pretty clear they had some training. >> yeah, my senior law enforcement officials are telling me, george, that it's pretty clear these men are paramilitary training. also this very interesting fact. apparently they told the carjacking victim the person that they carjacked that they were, in fact, the marathon bombers. now, law enforcement officials are saying this is the most tense urgent situation that you can think of. that this suspect number two who is the one with the white baseball cap is armed and dangerous and likely to die in a suicide attack. law enforcement offials say it could not be a more dicey, serious situation. also, george, we're also being given some guidance that law enforcement officials believe that these men were forced to ground in part by the release of those pictures and the video yesterday that created massive pressure on them and some law enforcement officials say that's why they took the action that they

pierre thomas, abc news, fort worth, texas. >> so glad you were watching.n me for ur one-hour special at 10:00 p.m. eastern tonight. murder, mystery, amanda knox speaks. an abc news exclusive. and i'll see you again tomorrow night right here. goodnight. "wheel's" in new york. wheel... of...

i want to go to abc's pierre thomas because there's a lpt about a package arriving at a senator's office with a deadly material inside. what can you tell us? >> reporter: sources are telling us tonight that a alert addressed to mississippi senator roger wicker tested positive for poison. these tests are notoriously unreliable but the letter is being tested again for a more definitive result. the package was intercept the at the mail facility and never reached the capital complex, but they're taking extra security precautions just in case. >> just to be clear, do we have any information about anyone could have come in contact with it? it can be extremely lethal. >> generally it needs to be ingested or inhaled to be dangerous to a person. we have no information that anyone pz been harmed so far, diane. >> i know homeland security is on top of it, as you are, pierre. we'll be back with you soon as you have more information to bring us tonight. so we'll take a break and be back with more breaking news tonight on "world news." back in a moment. w that feels. copd includes emphysema and chroni

i want to bring in abc's pierre thomas who has learned new details since the briefing toda. >> a senior law enforcement official tells me e wo suspects is seen in anher vio making a cellphone call around the time of the exns. they believe that the cellphone was used to trigger one of the explosions. the officials said a massive effort is under way to capture every cellphone call in that local area at the time of the bombings, to see if they can trace it back to the bomber. the source said it's a time-consuming process but a top priority. >> as you watch the tapes go by pierre, and you've studied these so often, tell us the kind of detail the fbi is asking everyone to notice. >> one of the things you can see as you look at the tape is that the black backpack is one critical piece of evidence. my sources are telling me that backpack is the one that they recovered the most material from. the other thing is that every piece of evidence in that frame, the hat, the coat, the pants, they want the public to look at that because there might be something that someone would notice. >> that's right

late today, officials told pierre thomas at abc news, that investigators had discovered female dna on fragments of one of the bombs, but that it's unclear whether it's from a victim, or someone who handled the parts innocently, or as a possible co-conspirator. >> thank you so much, brian ross. >>> we move on now, six months since that superstorm, hurricane sandy, slammed into the eastern seaboard, leaving so much destruction behind. here's a picture of the demolished boardwalk in seaside heights, new jersey, and tonight, six months later, the boardwalk, smooth, clean, and ready for summer. and you may remember, one of the most ravaged neighborhoods, was breezy point, queens. and abc's linsey davis is standing by there to show us the change tonight. >> reporter: good evening. here in breezy point, there were once 2,800 homes here. at this point, only 400 of them are occupied. in far too many locations, this is all that remains, crumbling foundations, stark reminders of what once was. >> the floodwater was in the vicinity of three feet. >> reporter: after wind, rain, and storm surge nea

. >> pierre thomas, it doesn't appear there was much chatter coming in before the attacks, but how about overall? what has the intelligence been like, pierre, tom cass as, in the last several months of international attacks in general? >> well, we know, again, that there was no specific credible threat before the boston marathon. we did an exclusive interview with the attorney general earlier this year and he talked about the fact that while al qaeda's central had been devastated and if you look at the overall terrorism pictures, one of the things that concerned him most is that you had so many splinter groups and also people being radicalized on the internet, and also people that would bring up lone wolves as they called them. he said that the terrorism picture was as difficult and energetic and dynamic as it had been since 9/11. al qaeda central devastated, but so much complicated in terms o the number of things he said he had to worry about and again, every day he was going over to the fbi and that was the first thing he did to get his briefing with the fbi director. >> pierre, when w

i wanted to ask you somebody that pierre thomas and our investigative team reported in to us late todaythere's indication at this point that the brothers might have had more help than just the internet in making these bombs? >> reporter: that's right. some investigators are saying that they believe that the older brother must have had outside training to help make these bombs but they just can't prove it yet. >> fast-moving again tonight. linsey davis in boston. linsey, thank you. >>> and with so much attention with the terror in boston, late today, another unsettling image. a very stark reminder of september 11th. an incredible discovery. wedged between two buildings in new york city, a piece of one of the planes from 9/11, the landing gear, just blocks away from ground zero, almost 12 years later. abc's ron claiborne is in downtown manhattan tonight with the images. ron? >> reporter: david, a surveying team inspecting the narrow passageway between these two buildings, one of the buildings on the left, a mosque. made a discovery. the landing gear had the imprint from boeing. both of th

pierre thomas is there. good morning, pierre. >> reporter: good morning, george. it's unheard of for top law enforcement officials to be executed in a small town like this. today, the fbi, atf, and local marshals are here to help solve these shocking murders. an army of police are trying to find out who broke into the home of mike mclelland, the county's top prosecutor, and murdered him and his wife in cold blood. >> it's unnerving to the law enforcement community. it's unnerving to the community at large. >> reporter: it was weeks ago that he had vowed to find the killer of one of his top deputies, assistant district attorney mark hasse. in late january, he was executed in broad daylight by two suspects dressed in black s.w.a.t. gear. >> i hope that the people that did this are watching, because we're very confident that we're going to find you. we're going to pull you out of whatever hole you're in. >> reporter: sources tell abc news that an assault-style rifle was used to fire multiple shots at mclelland and his wife. prosecutors are reviewing cases looking for

abc's senior justice correspondent pierre thomas has been following it all from washington. >> reporterod morning. the older brother is the subject of intense focus today. my sources are telling me that tamerlan tsarnaev may be key to unraveling the key behind these attacks. in 2011, the russian government became concerned about tamerlan, 26, suspect number one, travel from the u.s. back to russia to connect with radicals there. they asked the fbi to investigate. >> my son would never do this. it is a set up. he was controlled by fbi like for five, three, five years. they knew what my son was doing. >> reporter: the fbi acknowledged that it interviewed tae taermlan at the request of the russians. after looking at his phone records, and websites he visited, he found no ties. >> too many people in this country, just like him, that are touching extremist websites, espousing things that aren't particularly kind to americans. that's not against the law here. >> reporter: taermlan's father said that his sons couldn't have planned the attacks. they never knew that a dark side of the two brothe

abc's pierre thomas is in kaufman, texas, with the very latest. ng. >> reporter: good morning, amy. in just a few hours prosecutors will be back here at the courthouse under tight security

pierre thomas joins us with more. pierre, good morning to you. >> reporter: in many ways, this is the quest for the american dream turned nightmare. immigrants of the russian caukasus, the brothers came to the u.s. with their parents, attempting refugee status and thrived. >> the high school student i knew and my classmates knew is the exact opposite of the person that's been committing these crimes. >> reporter: their mother, speaking to russian television, refuses to believe her sons are vicious killers. >> it's impossible. impossible for them -- for both of them to do such things. i'm telling that this is a setup. >> reporter: older brother, tamerlan, 26, was a star athlete and pianist. also a champion golden gloves boxer. with dreams of competing in the olympics for the american team. younger brother, dzhokhar, became an american citizen last year on september 11th. once a life guard, he was also an all-state wrestler and was at the university of dartmouth on scholarship. >> never, ever imagine that somehow, the ch

i'm joined here by martha raddatz, also pierre thomas in washington. let me begin with you, pierre. intelligence officials, brian said, are not ruling in or ruling out anything at this point. one thing so mystifying. no one has stepped forward to claim responsibility. >> reporter: i spoke to a senior official who said typically in the hours after a bombing like this, terror organizations like to claim responsibility. they want the credit for their deadly work. a number of people were interview ed overnight. some associated with that saudi student and still don't know if he had anything to do with the bombing but out after an abundance of caution they're trying to dissect his life but piecing together the bomb remnants is key because they have air vast catalog of past bombing incidents and will compare it to whatever information they can get about these devices and come up with a list of potential suspects. >> pierre, this is exactly the kind of attack homeland security officials have been worried about over the last several years, not all that sophisticated but attacking softing its