U.S. Ambassador to Libya Chris Stevens and three of his staff members died after militants attacked the U.S. consulate in Benghazi, Libya, in September. The attack was attributed to an act of terror, though the ambassador was said to have died from smoke inhalation.
FBI Director Robert Mueller met in Libya with Prime Minister Ali Zidan, intelligence and justice officials to probe the incident Thursday, The Tripoli Post revealed.
"The director's visit was an opportunity to discuss ongoing cooperation on a number of issues," an FBI official was quoted by the newspaper as saying on condition of anonymity.
U.S. lawmakers were critical of the security in the region and the response to the September attack. U.S. Deputy Secretary of State William Burns told Senate leaders last month the State Department learned "some very hard and painful lessons" from the attack on the consulate in Benghazi.
U.S. Secretary of State Hillary Clinton is scheduled to testify Tuesday before the Senate Foreign Relations Committee on the incident.
This week, the Italian government announced it was temporarily closing its offices in Benghazi after Italian Consul General Guido De Sanctis was attacked.
Gunmen fired on his vehicle as it left consulate grounds Saturday, though he was uninjured.