At least 10 people have been killed and almost 40 wounded when forces from Libya's two rival governments clashed with armed fighters in two large cities on Wednesday, officials have said.
Supporters of Islamic State of Iraq and the Levant (ISIL) and other armed groups have exploited the turmoil in Libya, where two governments and parliaments are fighting for control four years since the ousting of Muammar Gaddafi.
In the eastern city of Benghazi, nine soldiers were killed when fighting the Majlis al-Shura, an umbrella of armed groups including Ansar al-Sharia blamed by Washington for the storming of a US diplomatic compound in 2012. US ambassador Christopher Stevens, along with three other Americans, was killed in the deadly attack.
At least 30 soldiers were wounded, a military spokesman said.
Libyan forces allied to the internationally recognised government based in the country's east have been fighting rebel groups in the port city since last year.
Backed by helicopters, army special forces took back several government buildings in Libya's second-largest city previously held by Majlis al-Shura, said the spokesman.
The army has gained some territory but clashes continue almost daily despite repeated claims by top army commander Khalifa Haftar that his forces were dominating.
ISIL's growing influence
In the central city of Sirte, ISIL fighters fought with forces sent from the western city of Misrata allied to a self-declared government that runs from the capital, Tripoli, officials and residents said.
Taking advantage of the security vacuum, ISIL fighters seized Sirte, Gaddafi's home town east of Tripoli, earlier this year.
One member of the Misrata-based Brigade 166 was killed and seven were wounded on Wednesday, Jamal Zubia, a spokesman for the Tripoli-based government, said in a message on social media.
ISIL said in a Twitter message its fighters had seized a camp of the Misrata forces in southeast Sirte.
The group published pictures purportedly showing its fighters at the camp, seizing several vehicles. A resident said the camp seemed to be in the hands of ISIL.
ISIL fighters have in recent months claimed responsibility for several attacks including the storming of a Tripoli hotel and the murder of dozens of Egyptian and Ethiopian Christians.