It was the first time guerillas have attacked General Mohammed Latif's Falluja Brigade since it set out to pacify Iraq's most rebellious town west of Baghdad last month following fierce fighting between US troops and insurgents.

Officers in the force told Reuters 10 people were wounded in the attack.

Witnesses said the mortar attack hit a camp housing security forces. They said Latif was not in the area at the time and no US forces could be seen.

Fiercely anti-American Falluja has been relatively calm since Latif and other generals offered to help tame the area where roadside bombs and ambushes have dogged American troops in the area.

The US wants Latif to rein in guerrillas, help capture or kill foreign fighters and collect weapons from rebels. He describes Falluja as a town of peace-loving people and believes US troops should go home.

The attack will put Latif's security forces through their first major test and raise questions over whether the Americans will redeploy their positions closer to the town.

US troops are still within striking distance of Falluja but the American military has tried to keep a low profile to give attempts to calm Falluja an Iraqi face.

Members of the force said a joint patrol with American troops had been scheduled to pass through Falluja at the time of the attack.

US troops launched an offensive on the town after four US contractors were killed by guerillas and then mutilated and dragged through the streets by residents on March 31.

After weeks of fierce fighting between the Americans and guerillas which killed hundreds of Iraqis and scores of US troops, the US military struck a deal with Latif, a former general in Saddam Hussein's army.

Set up under a peace agreement to end the clashes, the 2,000-strong Falluja Brigade is composed mainly of Baathists who served in Saddam's army, which was disbanded by US forces.

Pacifying Falluja, a volatile mix of Saddam loyalists, Muslim militants and tribes, has been one of the biggest challenges facing American troops.

Eleven Iraqis, including women and children, were killed on Tuesday in clashes between US forces and insurgents near Falluja, hospital sources said.