EL-ARISH, Egypt (AP) — Militants attacked three police checkpoints in the restive northern Sinai Peninsula late Tuesday, killing at least six policemen and wounding eight other officers, security officials said.

The officials said at least four militants were killed, including a suicide bomber who set off his explosives at one of the checkpoints attacked in the coastal city of al-Arish late Tuesday. The officials agreed to provide the details only if not quoted by name because they were not authorized to brief the media.

No group claimed responsibility for the attacks, although they bore the hallmarks of the Islamic State group.

Egypt’s government has been battling Islamist militants centered in northern Sinai. The insurgency intensified after the military ousted an elected but divisive Islamist president amid mass protests in 2013.