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CBS News has learned the DNA and fingerprints on bomb fragments found at the Boston bombing scene do not match those of Tamerlan Tsarnaev's widow, Katherine Russell.
But Russell is still under scrutiny due to her proximity to the suspected Boston bomber, according to CBS News senior correspondent John Miller, a former assistant FBI director.
"I think they're very skeptical about (her story)," Miller said on "CBS This Morning." "But again, 'skeptical' isn't proof and that's why they're trying to work through that and I think that's why her lawyers are slowing that down."
Investigators are looking at a phone call between Russell and Tamerlan Tsarnaev just hours after the FBI released a picture of him. Miller said the "nature of that call" is of particular interest. Cooperative with police since the initial stages of the investigation, Russell has begun to communicate with law enforcement through lawyers.
Miller explained, "The other day they showed up at her family's place where she's staying now in Rhode Island with a court order to take DNA samples, hair samples and so on to compare with what they found on the bomb.
"From that point on what's being put out is that she's no longer cooperating," Miller said. "I think what we're actually seeing is lawyers doing their job, which is she retained counsel and it was very clear she was developing into a potential target of this investigation and they basically said, 'If you want anything -- it's not that we're not cooperating -- but bring it to us and we'll send you back an answer.'"
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