A suicide car bomber killed six members of an Iraqi police unit when he struck their checkpoint near Baghdad today
Police said several others were wounded in the attack near Balad, 80km north of the Iraqi capital.
It was the latest attack on members of the Salahuddin Awakenings Council, an alliance of tribes in the Sunni Arab province of Salahuddin opposed to al-Qaeda's religious extremism.
Similar councils have been established in Anbar and Diyala provinces.
The US military has signed up hundreds of tribesmen and even members of Sunni Arab insurgent groups to form "concerned citizens" groups to battle al-Qaeda.
