Afghan officials say six police officers, including a district police chief, have been killed by gunmen affiliated with the Islamic State group in the restive eastern Nangarhar province, which borders Pakistan.

Attaullah Khogyani, spokesman for the provincial governor, says that IS-affiliated insurgents attacked the administrative headquarters in Haska Mina district at 2:00 a.m. Saturday.

He says 15 IS fighters were killed and seven wounded in the battle that followed.

Hazrat Hussain Mashreqiwal, spokesman for the Nangarhar police chief, says six police officers were wounded.

Nangarhar has long been plagued by insurgent groups. Last year militants there claimed allegiance to IS and the Taliban sent fighters against them.

In recent months, government troops backed by air strikes have claimed success against IS fighters, who are believed to be former Taliban members.