Transcript for Accused Boston Bomber Turning Point in Russia?
We begin with something new in the case of the boston bombings. Abc news has learned investigators believe they have located a possible seed bed of extremism. A mosque overseas, and two men, radical militants, who may have inspired the older brother to pull off that attack. Abc's chief investigative correspondent, brian ross, has the latest details and the new clues. Reporter: U.S. Authorities now believe a turning point for tamerlan tsarnaev came last year in the russian republic of dagestan, at this mosque known to be a gathering spot for extremists. Russian security services have told their american counterparts the boston resident was seen meeting and leaving from the mosque with a known chechen terror recruiter, mansur nidal, who was killed in a stand-off with authorities while tsarnaev was in dagestan. The chechen insurgency is part of a larger violent group that has used a reign of terror in its efforts to impose islamic law and values across portions of russia. Who moved to dagestan earlier and became part of the chechen terror group. Plotnikov was killed by russian authorities in july of last year. Tsarnaev last the country two days later for boston. Russian authorities asked the u.S. To investigate tsarnaev two years ago, but did not provide specific new details until after the marathon attack. President obama said today he's asked for a full intelligence review of what happened, but defended the performance of american law enforcement. Based on what I've seen so far, the fbi performed what it's supposed to be doing, but this is hard stuff. They're investigating whether friends or relatives knowingly or unknowingly helped dispose of evidence in the days after the bombing. They're among the individuals the fbi still calls persons of interest. Thank you, brian.
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