A US air strike has targeted the leader of the Islamic State (IS) group in Libya and probably killed him, the Pentagon says.

Iraqi national Abu Nabil, also known as Wissam Najm Abd Zayd al-Zubaydi, was a "long-time al-Qaeda operative", it said.

The strike took place on Friday and targeted a compound in Derna.

The Pentagon said the strike showed that it would go after IS leaders "wherever they operate".

'Degrading IS'

News agencies have quoted US officials saying they are confident Nabil was killed.

"Nabil's death will degrade Isil's ability to meet the group's objectives in Libya, including recruiting new Isil members, establishing bases in Libya, and planning external attacks on the United States," Pentagon spokesman Peter Cook said, using a different name for the group.