Iraqi officials say a double bombing has killed seven people in Tikrit. Police officials say the attack took place on Saturday morning, when a roadside bomb exploded in a commercial street in the northern city of Tikrit.Minutes later, a car bomb struck policemen who had arrived to inspect the first blast. Tikrit was the stronghold of former Iraqi dictator Saddam hussain. The officials say five policemen and two civilians were killed and 18 people were wounded in the bombings.