Libyan authorities will bring the killers of the U.S. ambassador and three other personnel to justice, the head of the national assembly, Mohammed Magarief, said on Wednesday
"We confirm that no one will escape from punishment and questioning," Magarief told a news conference broadcast live on Al Jazeera television.
He also apologised to the United States for the attack on its consulate in Benghazi in which the diplomats were killed.
Magrief promised that all foreigners in Libya would be protected.
"Diplomatic missions, foreign companies and citizens of foreign countries in Libya are under the protection the Libyan country and security forces," he said.
Deputy Interior Minister Wanis al-Sharif earlier accused supporters of the late Libyan leader Muammar Gaddafi of carrying out the attack.
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