Attacks in Iraq killed at least 24 people on Tuesday, including several civilians who died when five car bombs exploded in the capital, security and medical officials said.
The attacks were the latest in a surge of unrest that has left more than 4,200 people dead this year.
Near the northern city of Mosul, gunmen ambushed a vehicle carrying unarmed policemen and raked them with machine guns, the sources said.
Six policemen were killed in the attack and two were seriously wounded.
In the evening five car bombs exploded in various parts of Baghdad, including the centre and the northeast of the capital, killing at least 16 people, most of them civilians, and wounding 50, the sources said.
Earlier in the day a provincial official was shot dead in Baghdad while a soldier was killed west of Mosul by an explosive device, they added.
Also on Tuesday suicide bombers wearing explosive belts attacked a police station in Fallujah, west of Baghdad, and traded fire with the security forces.
Three of the bombers were killed when their explosives blew up while the fourth suspect was shot by police, the sources said, adding that 12 policemen were wounded.
Violence kills 24 in Iraq