CAIRO (AP) — Libyan authorities say six people were killed when a suicide car bomber struck a checkpoint in eastern Libya, in an attack claimed by the local affiliate of the Islamic State group.

The bomber targeted the eastern gates of Ajdabiya, said Fawzy al-Mansouri, head of the city operations room. He added that members of one family were among the dead and that five soldiers were wounded. IS claimed responsibility on Friday on its Aamaq news agency.

The attack comes less than a week after a U.S. airstrike killed two al-Qaida militants, including a top recruiter, Musa Abu Dawud, in southern Libya.

Islamic extremists expanded their reach across Libya after country was plunged into chaos following the 2011 uprising that ousted and killed longtime ruler Moammar Gadhafi.