those murders? >> no, because we had been in serious dialogue about him becoming a professional boxer. he definitely had become disillusioned and he was very hesitant to do it. >> reporter: allan says he gave fbi agents todashev's name. todashev was shot by an fbi agent after allegedly implicating himself in the murders. what questions do you have over the death of ibragim todashev? >> i think everybody has questions. that's a bizarre story and situation. it's very hard to believe. >> reporter: a seemingly bizarre coincidence of two unthinkable crimes and a cast of characters all connected to tamerlan tsarnaev and his days working out at a boston gym. deborah feyerick, cnn, boston, massachusetts. the middlesex district attorney's office is heading that investigation into the triple murder case. it says it's conducted a thorough investigation from the start and says that