BAGHDAD (AP) — Iraqi authorities say a bomb exploded near the house of an anti-al-Qaida militiaman south of Baghdad, killing him, his 8-year-old son and another family member.

A police officer said that the blast hit early Sunday in the town of Iskandariyah, 50 kilometers (30 miles) south of Baghdad. The Sunni fighter's wife and two daughters were also wounded.

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

Since the height of Iraq's insurgency in 2006-2008, Sunni Arabs who joined forces with the U.S. military to fight al-Qaida have been favorite targets for Sunni militants who consider them traitors.