A roadside bomb struck a car being driven by a police colonel, killing him and his two children Sunday in Tikrit, north of Baghdad. Lt. Colonel Haitham Akram, who was driving his two young sons in his private car was struck when a roadside bomb hit the vehicle at 8 a.m., engulfing it in flames, police First Lt. Udai Ahmed said. A second car parked nearby was also set ablaze, killing two girls aged 7 and 9, Ahmed said. Roadside bombs hit three separate US convoys in central Baghdad on Sunday morning, wounding a total of five soldiers, military spokesman, US Sgt. First Class David Abrams, said. In other parts of Baghdad on Sunday, a suicide car bomb hit two police vehicles at 11:30 a.m. in central Al-Tahrir Square, killing two police officers and two civilians, said police Maj. Mohammed Younis. The blast also wounded four policemen and seven civilians and damaged many shops in the area, he said. In northern Iraq, a suicide car bomber rammed into a US military convoy at 9:15 a.m. in the oil-rich city of Kirkuk, killing two civilians and wounding 13, said police Capt. Farhad Talabani.