US authorities added the name of the Boston bombing suspect Tamerlan Tsarnaev to a terrorist database 18 months before the explosions, but did not follow up their inquiry.
Officials say the CIA made the request to add Tamerlan's name after the Russian government contacted them with concerns he had become a follower of radical Islam.
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After Roy Hodgson's resignation following England's humiliating exit from Euro 2016, who are the leading contenders to replace him?
The beleaguered Labour Party leader is clinging onto power in the face of as many as 150 MPs voting to remove him from the top job today.
Mr Osborne said he is "not the person to provide the unity my party needs".