TRIPOLI, Libya — A security official says the leader of an Islamic extremist militia in Libya suspected of involvement in an attack in Benghazi that killed the U.S. ambassador has been shot.

Sufyan bin Qumu, a former Guantanamo Bay detainee, was shot Sunday in the area of al-Thruwn in the eastern city of Darna, a stronghold of Islamic extremists.

The security official says he was taken to a nearby hospital and is in the intensive care unit. He spoke anonymously in line with regulations.

Residents of eastern Libya, where the September attack against the U.S. Consulate took place, have been standing up to Ansar al-Shariah. Protesters stormed the group's compound in Benghazi days after the attack.

No suspects have been named in the attack that killed Ambassador Chris Stevens and three other Americans.