The US did not inform the Libyan government about the arrest of the suspected ringleader of the 2012 on an American diplomatic compound, according to a Libyan minister.
The US Ambassador to the United Nations, Samantha Power, notified the UN Security Council of the capture on Sunday of Ahmed Abu Khatallah by US special forces.
She said an investigation had not only implicated him in the 2012 raid but also planned "further armed attacks" against US personnel.
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Rain will clear eastwards through Sunday but it will remain blustery.
Donald Trump has indicated he does not intend to block the release of thousands of secret files about the assassination of John F Kennedy.
Storm Brian will track off into the north sea later tonight. Blustery tomorrow.