BENGHAZI, Libya (AP) — The extremist Islamic State group has claimed responsibility for an attack on a checkpoint in western Libya that killed at least four people.

IS made the announcement in statement carried by its Amaq news agency on Saturday. The attack took place outside the town of Zliten on Thursday.

The United Nations Support Mission in Libya and the U.N.-backed government in the west condemned the attack.

Islamic extremists expanded their reach in Libya after the 2011 uprising plunged the country into chaos and toppled and later killed longtime ruler Moammar Gadhafi.

IS was driven from its main stronghold, the coastal city of Sirte, in 2016 and fled inland.

Libya is currently split between rival governments in the east and the west.