The move threatened to complicate the US force's relations with its Kurdish rebel allies who entered the city without a fight on Friday and for whom the existing mainly Sunni Arab police are a hated symbol of the old regime.

But the small US force, which is still awaiting reinforcement after entering Mosul several hours after the Kurds, had few options in the face of the deadly clashes that have gripped the city.

"Tonight, we are putting the police back on the streets," said the commander of US forces in the city, Lieutenant Colonel Robert Waltemeyer.

"I want to make it clear those police are under my protection."

Waltemeyer said his troops were also looking to create a new multi-ethnic force to guard key infrastructure in this sprawling city of some 1.5 million people.

Property-owners in each neighbourhood would be asked to establish their own protection against looters, he added.

But the move to coopt the existing police sparked fury from Kurdish residents who had greeted the collapse of Saddam's regime with jubilation.

As police officers gathered for a briefing at US military headquarters here, a grief-stricken Kurd turned on one of them, accusing him of murdering two of his brothers.

"All of these officers are traitors, supporters of Saddam and the Baath party," the protestor screamed.

Mosul's Sunni Muslim Arab community was widely seen as a bastion of support for Saddam and the ouster of his regime has sparked a frenzy of score-settling in the city.

Hospital sources say as many as 20 people have been killed and some 200 wounded in the violence, which has seen the divided communities establish rival roadblocks across the city.

Kurds insist the violence is understandable given the community's decades-long repression by Saddam.

"It is the revenge of the Kurds, the old historical hatred which has arisen," male nurse Fakher Omar told AFP.

"Saddam Hussein controlled the population but each one has had a member of their family killed by the regime. Now that there is no more authority, they are taking vengeance."

But Arab residents, who fear the Kurds want to make their city part of a breakaway autonomous region, accuse the rebels of being responsible for the looting.

"The Kurds of Mosul or those from the north have come to attack us under the eyes of the impassive Americans," said one Arab resident, who has taken up arms to resist.

"The imams called on the population to form a civil militia to defend our goods and our families."

US special forces troops have relied heavily on their Kurdish allies in their battles with government forces in northern Iraq.

But the association has meant they have met with a stony reception from the region's non-Kurdish population.

A patrol of four light armoured vehicles was met with a deadly silence from onlookers Saturday, few of whom replied to the greetings of the US troops.

"I have a message for the Americans: I blame them for all that occurred," said Arab doctor Zaid al-Tahid.

"They pushed the peshmerga (Kurdish fighters) to make all this damage. They want to invade us not to release us."

It is an accusation that US commanders are keen to shake off, faced with the concerns not just of Iraqi Arabs, but also of neighbouring Turkey, which is fearful of the impact on its own large Kurdish minority.

"I want to make it clear that Mosul is not the single prize of any single ethnic entity," said Waltemeyer, adding that he expected US troop reinforcements to arrive in the coming days to end his force's reliance on Kurdish rebel support.

SPACE.WIRE