Bomb attacks and shootings in central Iraq on Friday killed four people, including a police colonel and an army officer, security and medical officials said. In Baghdad, a roadside bomb at the Rashid vegetable market on the capital\'s southwest outskirts left one person dead and at least three wounded, according to an interior ministry official and a medical source. Gunmen also shot dead a police colonel in the Shaab neighbourhood of north Baghdad while he was leaving work, security and medical officials said. In the former rebel bastion of Fallujah, gunmen killed an army intelligence captain in the centre of the city on Friday morning, Colonel Mohammed Dulaimi from the provincial security command centre said. Doctor Assem al-Hadithi at Fallujah hospital confirmed the death. And in the town of Baladruz, north of Baghdad in restive Diyala province, a roadside bomb struck the car of an anti-Qaeda militiaman, killing the fighter, a local police colonel and a medic said. The fighter was a member of the Sahwa, a collection of Sunni tribal militias that sided with US forces against Al-Qaeda from late 2006, helping turn the tide of Iraq\'s insurgency. The violence came a day after bombings across the capital killed 17 people, while shootings in the north of the country killed three others, underlining persistent security concerns in Iraq despite dramatically lower levels of violence compared to the brutal confessional bloodshed of 2006-2007.