Medical and security sources told Reuters on Thursday that gunmen have killed an American citizen working at an international school in the Libyan city of Benghazi.

According to the report, the attackers shot the man, who was a teacher at the Benghazi school, as he exercised in the morning, the sources said. No one claimed responsibility for the shooting. The U.S. ambassador to Libya three other Americans were killed in late 2012 when Islamist militants assaulted the U.S. consulate in Benghazi.

This reported incident has happened on the heels of the Obama administration claiming the U.S. and Libya’s relations have improved and are now “normalized” enough for the  United States to lift the ban on Libyan to work in the United States.