Gunmen kill American in Libya's Benghazi: sources

TRIPOLI (Reuters) - Gunmen have killed a U.S. citizen working at an international school in the Libyan city of Benghazi, medical and security sources said on Thursday.

The attackers shot the American man, who was an instructor or teacher at the Benghazi school, while he exercised in the morning, the sources said.

No one claimed responsibility for the shooting. The U.S. ambassador to Libya was killed in late 2012 when Islamist militants assaulted the U.S. consulate in Benghazi.

(Reporting by Ayman al-Warfalli in Benghazi; Feras Bosalum in Tripoli; writing by Patrick Markey)