Baghdad, Iraq (CNN) -- Gunmen wearing Iraqi army uniforms stormed at least four houses, pulled the residents outside and shot them -- killing four, police in Baghdad said.
The incident took place Monday in the town of Yusufiya, about 30 kilometers (18.6 miles) south of Baghdad. The gunmen pulled six men out of their houses and sprayed them with bullets. Four men were killed immediately, and two were critically wounded.
Iraqi security forces believe those killed were members of an awakening council.
Awakening councils, also known as the Sons of Iraq, were established by Sunni Arabs to reduce violence and provide security for residents in certain areas of the country. Council members are frequent targets of al Qaeda in Iraq.
Separately, a roadside bomb struck a vehicle in eastern Baghdad on Monday, injuring a senior police official and killing his driver. Another member of the police was wounded in the blast, Baghdad police said.