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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Billionaire Microsoft co-founder Paul Allen has claimed discovery of the Japanese battleship Musashi that was sunk by the US Navy in 1945.
Friday will be mostly dry with sunny spells for much of the UK. Temperatures will be mild across the country.
Some famous Liberal Democrat names will be fighting for their political lives in the election, now just over two months away.