A Libyan hospital official says two protesters were killed as hundreds of demonstrators attacked militia compounds in Benghazi, angry at the unchecked excesses of armed groups in the eastern city including last week's killing of the U.S. ambassador.

Mohammed al-Fakhri, manager of al-Hawari hospital, said Saturday that two young men died and about 30 were injured in overnight clashes near the headquarters of the Rafallah Sehati brigade.

It was the third compound protesters attacked after breaking off from a huge march in the center of the city, part of a growing backlash against the militias. A building used by the Islamist group Ansar al-Shariah, linked to the killing of Amb. Chris Stevens, was among those overrun.