The State Department on Friday designated two Libyan groups, including one led by a militant once held at Guantanamo Bay, as terrorist organizations and said they were involved in the deadly attack on U.S. diplomatic mission in Benghazi.
The groups are Ansar al-Sharia in Benghazi and Ansar al-Sharia in Darnah. Their leaders, Ahmed Abu Khattalah and Sufian bin Qumu, were designated as global terrorists by the State Department.
Bin Qumu was captured in Pakistan and held at Guantanamo for five years before being released to Libyan authorities in 2007.
The State Department also gave the terror designation to a Tunisian group, Ansar al-Sharia in Tunisia, and to its leader, Seifallah Ben Hassine.
The department said that group was involved in an attack on the U.S. Embassy and an American school in the Tunisian capital on Sept. 14, 2012, three days after the attack in Benghazi.
Four Americans, including Ambassador Christopher Stevens, were killed in the Benghazi raid.
The State Department said in November that it had been quietly offering rewards of up to $10 million for information leading to the arrest or conviction of anyone involved in the Benghazi attack.
The department said Friday it was committed to working with the Libyan government to bring those responsible for the attack to justice.