WARNING-STORY CONTAINS GRAPHIC IMAGES<br/> <br />ROUGH CUT (NO REPORTER NARRATION)<br/> <br />Gunmen shot dead an American chemistry teacher working at an international school in the Libyan city of Benghazi, medical and security sources said on Thursday (December 5)<br/> <br />It was not immediately clear who was responsible for the killing.<br/> <br />Libyan special forces have been battling militants from Ansar al-Sharia in Benghazi. U.S. officials blame the group for attacking the U.S. consulate in the eastern city in September 2012, killing the ambassador and three other Americans.<br/> <br />Security sources said three soldiers were also killed in separate attacks on Thursday in Benghazi.<br/> <br />Two years after a NATO-backed uprising ousted veteran leader Muammar Gaddafi, Libya's armed forces are struggling to contain militias, former fighters and Islamist militants who control parts of the vast oil-producing country.
