At least 31 people were killed and hundreds more were wounded in Tripoli after a demonstration calling on unruly militias to leave the Libyan capital turned violent on Friday, the health minister said.

The militias are holdovers from the 2011 uprising that ousted dictator Moammar Gadhafi and are a powerful force in the increasingly lawless North African country.

Libya has expelled more than 900 soldiers from its fledgling army for having fought for now slain dictator Moammar Gadhafi during the 2011 uprising, a military spokesman said Thursday.

A total of 915 personnel of all ranks have been stripped of their uniform by the Commission for the Integrity and Reform of the Armed Forces, general staff spokesman Ali al-Sheikhi said.

Two attacks in Libya's Benghazi Thursday killed an air force chaplain and a former police officer, a security official said, the latest in a wave of violence targeting soldiers and police.

Sheikh Muftah al-Fitouri, who preached at the city's Benina air base, was killed when an explosive device attached underneath his car detonated on Thursday morning, the official said.

Libya's top jihadist group, blamed for deadly unrest that includes attacking a U.S. mission, said Tuesday there will only be security in the increasingly lawless country if Islamic law is introduced.

"Stability and security are dependent on the application of sharia (Islamic law)," Ansar Al-Sharia said, explaining that this was its position in light of the "political bickering" in Libya.

Libya's prime minister on Monday promised more arms and other resources for security forces struggling to pacify the eastern city of Benghazi after a string of deadly attacks last week.

The cradle of the 2011 revolution that toppled veteran dictator Moammar Gadhafi has seen a surge in shooting and bombings targeting security forces and Western missions in recent months.

Hundreds of Libyans took to the streets of the capital Tripoli and other cities Saturday to protest against a renewed mandate for the country's top political body, the General National Congress, next year.

The GNC is the fruit of the country's first free elections in July 2012 after the overthrow of longterm dictator Moammar Gadhafi's regime in October 2011.

A string of attacks in eastern Libya has killed a public prosecutor and three members of the security forces in less than 24 hours, judicial and medical sources said Saturday.

Since the ouster of veteran dictator Moammar Gadhafi in October 2011, eastern Libya has been hit by a wave of bombings and shootings, mostly targeting security officials.

Dozens of asylum-seekers on a boat that sank near the Italian coast last month with the loss of 366 lives were raped and tortured in Libya before starting their journey, the police said on Friday.

A group of 130 migrants from Eritrea were held for ransom in the desert, according to testimony from survivors that led to the arrest of a Somali man in Italy accused of being one of the traffickers.

Two people were killed and 29 others wounded in deadly clashes between rival Libyan militias in Tripoli sparked by the death of one of their leaders, the health ministry said Friday.

Libya has been plagued by deadly unrest since NATO-backed rebels toppled the regime of now slain veteran dictator Moammar Gadhafi in 2011.

A Libyan intelligence officer was killed in a car bombing in the eastern city of Benghazi Wednesday three days after a colleague died in the same way, a hospital source said.

"Officer Abusif al-Mabruk succumbed to his wounds" several hours after the blast, Al-Jala hospital spokeswoman Fadia al-Barghathi told Agence France Presse.