TRIPOLI - Two of four Americans killed in Libya on Tuesday died in a shooting during an attempt by US forces to evacuate staff from a safe house, Libya's Deputy Interior Minister Wanis Al-Sharif said.

US consular staff were moved to the safe house after an attack on the consul building in the eastern city of Benghazi in which the ambassador was killed, minister Wanis Al-Sharif told a news conference.

A plane with US security units arrived from Tripoli to evacuate other staff but militants discovered the location of the safe house, he said.

"It was supposed to be a secret place and we were surprised the armed groups knew about it. There was shooting," he said.

Two American security personnel were killed in the shooting, Sharif said. Two other people were killed and between 12 and 17 wounded.

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