relatives of the tsaranevs says is the man who radicalized tamerlan and maybe dzhokhar, as well. what have you learned about him? >> reporter: we've learned a lot, recently. agents have been interviewing him. he is the man who tamerlan's relatives blame for influencing him. now, we're hearing from misha himself. this is from a reporter who interviewed him. the reporter says misha strongly denied influencing tamerlan negatively. he hasn't seen him in three years. here's what the reporter had to say. >> he was very, very, very intent on explaining he had nothing to do with any kind of radicalization. what he told me was, i was not his teacher. if i had been his teacher, i