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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The prime minister pitched her comments firmly towards unionists in her first campaign visit to Scotland ahead of the general election.
A police officer who spent six days crawling the London Marathon in a gorilla costume has finally completed the 26-mile route.
Nicola Sturgeon calls on voters to make sure "Scotland's voice is heard" and not "dragged back by the Tories" in upcoming vote.