get to yesterday's capture of dzokhar tsarnaev. tell us what it has been like for you in cambridge, the police presence and -- caller: from the marathon on it has been chilling. host: were you at a marathon? caller: no, i wasn't. all of yesterday was lockdown. that was chilling, too. nobody knew how long it was going to last. it was a very uneasy and reject a very uneasy feeling -- a very uneasy feeling. "the neweadline in york post," did you feel like you were hunkered down in cambridge even though most of the activity was in watertown? there was no one in the street, it was really hunkered down. if you were following on the radio or tv it was mostly in watertown but you were also warned to hunker down. it was an uneasy feeling throughout. everyone totally regrets the incident. it was horrible. host: thank you for your call. next we will go to george in staten island, new york. good morning. caller: good morning. i would like to say i think it is unbelievable a u.s. citizen rights onng given u.s. soil. no person should be held cap

as swat teams cordon off wide swaths of the city and surrounding towns to capture 19-year-old dzokhar tsarnaev. >> brown: we explore what's known so far about the brothers suspected in the deadly attack. >> suarez: we examine how investigators are trying to figure out whether the brothers acted alone or were part of a larger terrorist organization. >> brown: and we look at how technology allowed police and thpu t >> suarez: plus, we get the perspective of mark shields and david brooks on terror's return to u.s. soil and the rest of the week's news. nighrown: that's all ahead on s "newshour." >> major funding for the pbs newshour has been provided by: >> support also comes from carnegie corporation of new york, a foundation created to do what andrew carnegie called "real and permanent good." celebrating 100 years of philanthropy at carnegie.org. >> and with the ongoing support of these institutions and foundations. and... and friends of the newshour. >> this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. than

kwame holman bins our lti- part look at today's evolving story. >> reporter: 19-year-old dzokhar tsarnaev escaped the early morning gun battle in suburban boston that killed his 26-year- old brother tamarlen. that set into motion an unprecedented manhunt as a small army of local, state and federal officers fanned out through boston and its suburbs. the city was brought to a near standstill. more than one million people were urged to shelter in their homes. schools and mass transit were closed; amtrak service was shut down into the city. massachusetts governor deval patrick spoke at 8:00 am. >> there is a massive manhunt under way. a lot of law enforcement involved in that. to assist that we have suspended all service on the m.b.t.a., our public transit service, and this will continue until we think it's safe to open all or some of that. we're asking people to shelter in place-- in other words to stay indoors with their doors locked and notto open the door for anyo other than a properly identified law enforcement officer. and that applies here in watertown where we are right now. also camb

as swat teams cordon off wide swaths of the city and surrounding towns to capture 19-year-old dzokhar tsarnaev>> brown: we explore what's known so far about the brothers suspected in the deadly attack. >> suarez: we examine how investigators are trying to figure out whether the brothers acted alone or were part of a larger terrorist organization. >> brown: and we look at how technology allowed police and

they have knocked on the doors and checked on them and the manhunt under way for the suspect, dzokhar tsarnaev. >> he was in the city of watertown after midnight. the suspect number one was killed and that he was walking away after that fire fight. you see the timing of the entire evening there. it began with a robbery at a 7-eleven followed by the killing of a officer at m.i.t. and carjacked a driver of the suv and the fire fight, as we said fierce and it included grenades and firearms. police believe that dzhokhar had an automatic rifle and we know he is heavily armed going into the fire fight. they found a triggerlike device on the body on his brother that led them to believe that he could have a suicide vest which is one more reason why they are being so careful as they go house to house methodically in watertown right now. >> and one of the ironies that occur his brother was taken to the medical center, i believe, and that was where so many of the wounded of the boston marathon were taken, and they tried to save his brother. >> after 15 to 20 minutes, we don't ask who it is or what they d

younger brother, dzokhar tsarnaev remains outside of federal lockup outside of boston. the boston bombing, just one of the issues president obama spoke about today. he faced reporters on the 100th day of a second term in office. danielle nottingham reports for wjz, from washington. >> president obama suggested he'll consider military action against syria, if the international community confirms president bashar assad used chemical weapons on his own people. >> the proliferation risks are so significant that we don't want that genie out of the box. >> reporter: the president addressed his ongoing budget battle with congress, prodding lawmakers to find a compromise that will replace the automatic budget cuts. >> the only way we're going to lift it is if we do a bigger deal that meets the test of lowering our deficit and growing our economy. >> reporter: the president sounded more optimistic about immigration reform, saying he is confident that a bipartisan bill in the senate that beefs up border security and provides a pathway to citizenship, will make it to his desk. >>

police have identified them and investigators have identified him as 19-year-old dzokhar tsarnaev. his brothers killed overnight. >> just a moment. we're taking some pictures right now. you're seeing some activity that's taking place from our affiliate. this is the boston affiliate and this is the boston affiliate and it looks like there has been again some activity that's taking place. it's a chaotic scene and that's why you tend to see a lot of movement and a lot of running around. there have been helicopters circulating in the area and our scott cohn in watertown told me he's been looking at some of these, too, let's listen in. >> we'll just keep an eye on all of this, reid, and come back to you. >> john. thank you so much. let's go with candy at the breaking news desk. >> we have information and this is coming from boston's children hospital their main campus in the longwood medical area has been designated as locked down right now and they're doing that because of police and federal security and this is all related to the search for the suspect here in boston related to the ma

. >> woodruff: the surviving tsarnaev, dzokhar has reportedly told investigators that the brothers learnedmake the pressure cooker bombs from an online magazine called "inspire." it's published by al qaeda's affiliate in the arabian peninsula and includes a section called "open source jihad" that explains bomb-making techniques. the ideology that apparently sparked the attack remained on display on tamerlan tsarnaev's you-tube page: links to videos from, among others, an islamist fighter in the north caucasus. this afternoon the washington post reported that the c.i.a. asked to place tamerlan tasaranev's name on a watch list more than a year before the attacks. it was not immediately clear when his name was added to the list. but the post said it happened after the f.b.i. closed its initial inquiry. for more on what may have turned two young men into violent terrorists, i'm joined now by dr. jerrold post, who had a 21 year career at the c.i.a. where he founded the center for analysis of personal and political behavior. he's now a professor of psychiatry, political psychiatry and internatio