By Graham Smith PUBLISHED: 05:49 EST, 18 October 2012 | UPDATED: 07:02 EST, 18 October 2012 The leader of an Islamist group has been named as a commander in last month's attack on the U.S. consulate in Benghazi that killed three Americans including ambassador Christopher Stevens. Ahmed Abu Khattala, who heads the Benghazi-based Ansar al-Sharia group, was closely involved in the September 11 assault, according to Libyan authorities. Witnesses said they saw Abu Khattala lead the fatal assault, although his exact role has not been made clear. Suspect: Ahmed Abu Khattala, who heads the Ansar al-Sharia group, was closely involved in the September 11 assault on the U.S. embassy in Benghazi, according to Libyan authorities
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Ahmed Abu Khattala heads the Benghazi-based Ansar al-Sharia group
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Libyan officials say he was closely involved in the September 11 assault that killed four Americans including ambassador Christopher Stevens
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Consulate security entrusted to little-own British company
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How Obama handled aftermath of attack triggered war of words between the President and Mitt Romney in this week's second presidential debate
in Benghazi, Mr @placeholder said: 'No acts of terror will ever shake the