The self-declared government in control of the Libyan capital Tripoli has launched air strikes on Islamic State group (IS) fighters in the city of Sirte, officials and witnesses said on Monday.
Officials said the late Sunday night attacks were on a building where fighters had gathered. Witnesses reported they were accurate and said wounded militants had been taken to hospital.
Fighters allied to IS commanders in Iraq and Syria have been gaining ground in Libya, where two rival governments are battling for control and militants have taken advantage of the security vacuum.
IS fighters have gained ground in cities like Sirte and Derna to the east, challenging local armed groups and government forces alike. Sirte in particular has become a stronghold of Islamic State.
"Warplanes of the air force of the National Salvation government conducted airstrikes last night on an internal security building in Sirte," ministry of defense spokesman Mohamed Abdulkafi said by phone, referring to the Tripoli government.
"The strikes targeted a gathering of militants of Islamic State," he said. "No figures of casualties from the strikes have been reported so far."
One eyewitness in the city said the bombs hit a former headquarters of former ruler Moammar Gadhafi's security forces in Sirte.
"Many wounded Islamic State militants were taken to the local hospital," the witness said, asking not to be identified to protect their security. Black smoke rose over the city.
Libya is sliding deeper into internecine fighting between brigades of the former rebels who overthrew Gadhafi four years ago and have turned against each other since.
The self-declared National Salvation government has run Tripoli since its forces took over the capital in the summer, forcing the internationally-recognized government of Prime Minister Abdullah al-Thinni to operate from the east.
United Nations peace talks to broker a ceasefire and reach a power-sharing deal between the two factions have been struggling. European powers are pushing for an agreement, worried Libya is becoming a safe haven for militants and for people-smugglers ferrying illegal migrants to Europe.