TODAY | April 20, 2013
>> there are more questions than answers this morning as we know matt was just talking about that. one of the main questions, who are the suspects and what could have driven them to attack their adopted homeland. here with more on that is jeff rossen .
>> good morning again. for a week police have been focused on catching these guys and stopping the violence. now that that's over, the bigger questions remain. why would they do this and could there are clues from their past? this morning as you were just reporting, matt, we're learning more information from the fbi, federal agents questioned the older brother in 2011 after suspicions he was a following of radical islam and wanted to join underground groups. in the end as reported, the fbi found no terrorist activity. now family and friends are talking and filling in the blanks.
>> suspect is in custody.
>> reporter: the terror suspects, two brothers from russia who moved here ten years ago. 26-year-old tamerlan tsarnaev and 19-year-old dzhokhar. friday their own uncle denounced them.
>> he put a shame on the tsarnaev family. he put a shame on the entire chech chechen ethnicity.
>> reporter: they're father in russia refused to believe it. somebody cleared framed them he said. i don't know who framed them but they did. late friday he told nbc news he spoke his sons just after the marathon and they assured him they're okay and people who knew them thought they were okay too.
>> seemed to be regular kids like any other kids. i never noticed anything.
>> reporter: the older brother, tamerlan , was a boxer and even wanted to join the u.s. olympic boxing team. he had a wife and a 3-year-old daughter seen here being escorted by investigators. tamerlan was also an aspiring engineer who dressed well and drove a mercedes. he was a practicing muslim.
>> he was not devout practicing but just recently maybe two years ago he started praying five times a day, which is -- i don't see anything bad in it.
>> reporter: but he had a dark side . on his youtube channel , tamerlan posted a play list that included several extremist videos. this one showing what looks like g jihadist in the training. in a local boston magazine , tamerlan said i don't have a single american friend. i don't understand them. but the younger brother , dzhokhar, had lots of friends. diana went to school with him. was he ever violent?
>> not at all. he didn't seem religious at all. he didn't seem angry at the world. none of that sort at all.
>> reporter: dzhokhar went to school here at one of the most prestigious high schools in the area. other graduates include actors ben affleck and matt damon . people who knew dzhokhar here say he was a star wrestler. a nice, normal kid.
>> a regular teenager. he was sweet. always with his friends.
>> reporter: he wasn't a loner?
>> not at all.
>> reporter: dzhokhar is registered as a student at umass dartmouth . he says he's single listing his priorities as career and money. and declares as islam. he last logged in thursday at 9:04 p.m . just as policed launched a dragnet to catch him. knowing what you know, can you look back and say i missed that?
>> no red flags at all. nothing i wish i could have stopped from continuing.
>> now investigators are anxious to talk to the younger brother because they took him alive they have a much better chance now of piecing this all together in his own words and answering the big question, of course, which is why. so they can prevent future attacks and figure out what happened here.