A bomb hidden under a cart exploded in downtown Baghdad on Friday, killing two civilians and wounding six, police said.
The cart was left near a building, and the explosives apparently were detonated by remote-control at about 7.30am, police said, giving the casualty toll. Three cars parked nearby were damaged.
A booby-trapped car being towed by police also blew up in Saddam Hussein's hometown of Tikrit, killing two policemen and wounding four others, police said.
Police said they were removing the car after it was found parked near a market pockmarked with bullet holes and with bloodstained seats.
The explosion occurred about 8am as it was being pulled into the parking lot of the local police headquarters, officials said.
Tikrit is 130 kilometres north of Baghdad. The police officials all spoke on condition of anonymity because they weren't authorized to release the information.
Nobody claimed responsibility for the attacks. The US military has warned suspected Sunni insurgents led by Al Qaeda are seeking new ways to avoid stepped-up security measures that have dampened their ability to stage high-profile car bombings and suicide attacks. (AP)