school, college, from boxing now realize they never really knew them at all. the two brothers, outwardly so different, on april 15th are accused of acting together to bomb the boston marathon. incredibly, just days after the bombings, dzhokhar was spotted back on campus. betancourt saw him at the gym. >> we talked about the bombing for like about five minutes. he seemed very nonchalant. he didn't seem like nervous or anything. he seemed a little maybe tired and off. i asked him how he's doing. he was like yeah, i haven't been doing much lately, so i decided to come to the gym. >> reporter: betancourt says dzhokhar's reaction wasn't surprising. at the time. >> i was just talking about how, yeah, in iraq and afghanistan these things happen all the time and here it's crazy how this would happen. and he just said -- he was like, yeah, tragedies happen, man. these things happen around the world. like it's crazy. >> reporter: for julian pollard he hadn't thought much of his former boxing buddy until last