A double attack on Monday by a suicide bomber on a military checkpoint and group of labourers in the former Sunni rebel bastion of Fallujah killed seven people, police and medics said.
Twenty-nine people were wounded in the blasts, which occurred within minutes of each other at around 9:00 am (0600 GMT) in the centre of Fallujah, 50 kilometres (30 miles) west of Baghdad, officials said.
Captain Bashar Mohammed, chief of a police station in Fallujah, said the bomber parked his explosives-packed vehicle near a military checkpoint in the centre of the city.
He then left it and walked into a group of labourers and detonated his explosives vest. The car bomb exploded shortly afterwards, although no soldiers were among the wounded.
"He blew himself up among a group of day labourers," Mohammed said.
The casualty toll was confirmed by Ahmed Abdul Halim, a doctor at Fallujah General Hospital.
The security situation in Fallujah, once a hotbed of Sunni insurgency, has improved dramatically in recent years although militants continue to carry out sporadic attacks.
Since 2006, Sunni tribesmen and former rebels have joined forces with the US military against Al-Qaeda, greatly reducing the jihadists' presence in the area.