File photo of Libya Dawn fighters firing an artillery cannon at IS militants near Sirte March 19, 2015.

Unidentified warplanes carried out air strikes on Libya’s Sirte city, targeting areas controlled by Islamic State of Iraq and Syria (ISIS) militants in the south and west, a witness said on Thursday.

The strikes were the second on ISIS in the city this month. Neither of Libya’s rival governments nor other warring factions immediately claimed responsibility.

“We heard the warplanes around midnight, then there were massive explosions,” the witness said.

There were no immediate official reports of any casualties.

Libya is caught up in a conflict between two rival governments and their armed factions, leaving a security vacuum that has allowed ISIS militants to gain ground. They have secured a base in Sirte.

Western governments are pushing for a United Nations peace agreement to form a unity administration between the rival factions, fearing the turmoil is pushing Libya into becoming a failed state.

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