The threat of a city-wide refusal to work came in the wake of the US military's earlier confession that it took part in the "friendly fire" shootout, but only admitted to causing the Jordanian's death.

"We call on the people of Fallujah to participate in a major strike in the city to protest the massacre and to honour the souls of the martyrs starting from (Sunday)," a joint statement by political leaders and tribal elders said, without specifying how long the action would last.

They also called for an immediate meeting of the US-appointed provincial Governing Council, based in the nearby city of Ramadi, to discuss the situation and "take whatever steps are necessary and appropriate."

The statement also declared three days of mourning in the town from Sunday to commemorate the nine, who police said were killed when shooting erupted after two cars full of Iraqi security personnel and policemen gave chase to criminal suspects in a BMW.

Killed outright

When the chase reached a Jordanian-run hospital to the north of the town, all three cars ran into US soldiers who opened fire on them, a police spokesman said.

Eight members of the local protection force were killed outright along with two gunmen in the BMW, officials said, while an Iraqi policeman died overnight in hospital.

An Iraqi policeman looks into his dead colleagues' car

The joint statement hit out at what it called an "ugly massacre" allegedly committed by US troops against "people who have sworn to protect the brave city of Fallujah and its people."

The dead men had been "carrying out their duties in catching a bunch of criminals" and there were "no excuses for this massacre," it said.

A statement issued by the US army did not mention the deaths of the Iraqis, only that of the Jordanian, which it "deeply regretted". It said the clash in the flashpoint town early on Friday was under investigation and more information would be released as it became available.

"While conducting operations against enemy forces US soldiers were involved in an unfortunate incident near Fallujah in which a Jordanian hospital was damaged and at least one death of friendly personnel," the statement said.  

Returned for burial

On Saturday, the bodies of the dead men were transferred to a hospital in the nearby town of Ramadi and were due to be brought back to Fallujah for burial, a police source said.

Three attacks in five hours hit US troops around Fallujah later on Friday in an omen of worse to come if the US military failed to trust its Iraqi allies.

Residents of the town had gathered on Friday around the city hall and at the police headquarters to protest against the frequent bloodshed since Saddam Hussein was chased from power in April.

A spate of three attacks in barely five hours hit US troops around Fallujah later on Friday in what police and relatives warned was an omen of worse to come if the US military failed to trust its Iraqi allies.

Army silence

The US army announced an investigation into a similar incident in Baghdad a month ago, in which the military admitted two Iraqi policemen died from "friendly fire".

But since then no further details have been released about how that investigation has progressed, whether it has been concluded or whether any action might be taken against the soldiers if they were found to have acted inappropriately.

Army spokeswoman Specialist Nicole Thompson said on Saturday she had no knowledge of the publication of any findings.

Lieutenant Colonel George Krivo, a senior military spokesman, said determining what happened in Fallujah was not an easy task.

"There are a lot of facts to go through," he said.

In another development, a US convoy came under rocket-propelled grenade attack at noon on Saturday in the city of Tikrit, damaging their Humvee vehicle, bystanders told Aljazeera. 

It was unclear if the attack in Saddam Hussein's hometown caused any casualties, the witnesses said.