Suicide bombings against Libyan forces battling to oust Islamic State from their former North African stronghold of Sirte killed at least 12 fighters and wounded about 60 there on Thursday, a hospital spokesman said.
Forces, mainly composed of fighters aligned with a U.N.-backed government in Tripoli, have been closing in on the center of Sirte, where militants now control a shrinking residential area.
Since Aug. 1 the United States has been conducting air strikes to support them. As of Wednesday it had carried out 62 strikes, most recently against fighting positions and a vehicle-borne improvised explosive device, the U.S. Africa Command said.
Last week the forces, who are directed from Misrata about 230 km (143 miles) from Sirte, made big gains, securing a number of large buildings and complexes in the town that had been used by Islamic State snipers.
They claimed control over one of the final neighborhoods where Islamic State was present earlier this week, but as they have tried to advance further forward they have faced multiple suicide bomb attacks.
The casualties in Sirte on Thursday came from two separate suicide vehicle bombings, Misrata hospital spokesman Akram Gliwan said.
Islamic State imposed its rule over Sirte last year, extending its presence along 250km (155 miles) of Mediterranean coastline and creating its most important base outside Syria and Iraq.
Misrata-led forces began their campaign to capture Sirte three months ago, counter attacking after Islamic State advanced to within 100km (60 miles) of Misrata.