Updated

Iraqi officials say gunmen have killed four anti-al-Qaida fighters during an attack on a security checkpoint north of Baghdad.

Police officials say the attack early Friday took place when gunmen opened fire on a group of so-called Sahwa fighters manning a checkpoint near Dujail town. Dujail is 50 miles north of Baghdad.

A medic in a nearby hospital confirmed the death toll. All officials spoke on condition of anonymity because they are not authorized to talk to the media.

The Sahwa are Sunni Arabs who joined forces with the U.S. military to fight al-Qaida at the height of Iraq's insurgency. They have since been regularly targeted by Sunni insurgents who seem them as traitors.

Violence has ebbed in Iraq, but deadly attacks are still common.