As fighting raged, a two-week weapons amnesty produced derisory results with just over 1,000 arms and explosives turned in at local police stations, said US Central Command (Centcom).

Coalition forces started their new operation, codenamed Desert Scorpion, overnight, a military spokesman in Baghdad said.

"It's a larger operation," than Operation Peninsula Strike, said Sergeant First Class Brian Thomas, in reference to a six-day crackdown that ended Thursday and had been the army's biggest since the fall of Baghdad.

He said the operation extended over "several locations mostly in the north and northwest", of the country.

"We are targeting anyone who is striking against US soldiers. Some of them are (Saddam Hussein's former ruling party) Baath members and some of them are against our peace efforts,

He said that so far there were no reports of casualties, US or Iraqi. "We have detained people but we don't have any numbers right now."

Desert Scorpion would also fulfil a humanitarian role, Centcom said in a statement.

"This operation ... is designed to identify and defeat selected Baath Party loyalists, terrorist organizations and criminal elements while delivering humanitarian aid simultaneously.

"Combat operations will be followed by synchronized stability and humanitarian operations designed to assist a transition to Iraqi self-rule.

"These include engineer and civil affairs initiatives to repair damaged infrastructure, support the growth of police forces and local government and improve the lives of Iraq's citizens.

"The goal of Operation Desert Scorpion, in keeping with our ultimate mission, will be to help establish a permissive and secure environment and to facilitate a rapid transition to Iraqi self-sufficiency," Centcom said.

In Operation Peninsula Strike, which targeted areas of the Tigris valley north and northeast of Baghdad, Centcom said it killed 27 people in a single strike near the town of Balad.

Iraqi residents said another four people were killed in a separate part of the operation.

But although the operation netted a total of 397 suspects, all but 60 have already been released for lack of evidence.

In another major operation on Thursday, US forces killed 82 men in an air and land strike against a desert training camp near the Syrian border, according to witnesses who helped bury the dead.

US troops were also poised to launch a major clampdown on illegal weapons after a two-week amnesty which ended Saturday failed to persuade Iraqis to hand in the huge military arsenal which passed into civilian hands following the collapse of Saddam's armed forces.

The nationwide haul across the fortnight comprised just 123 pistols, 76 semi-automatic rifles or shotguns, 435 automatic rifles, 46 machine-guns, 162 anti-tank weapons, 11 anti-air weapons, and 381 grenades and other explosive devices, a Centcom statement said.

The meager showing, in a country known to be armed to the teeth, will either be destroyed or handed over to the future Iraqi army or police forces.

At a central Baghdad police station, commander Omar Zahed said he had only received six anti-tank weapons over the two weeks.

"The operation failed because Iraqis will never hand over their weapons until security is re-established," he said, echoing the widely-shared sentiment here that coalition troops may have toppled Saddam's bloody dictatorship but have brought chaos and mayhem to the country.

Under the new regulations which came in at midnight, it is an offense punishable by a year in prison to carry even small arms outside homes and businesses without coalition authorization.

On the first day of the new controls, US troops were alread manning roadblocks on the main international highway out of Baghdad to the Jordanian and Syrian borders, randomly stopping and searching cars, an AFP correspondent witnessed.

Earlier this week, the head of coalition ground forces, Lieutenant General David McKiernan, acknowledged a serious crackdown on violators of the new policy would be necessary to persuade ordinary people to comply.

"I would expect a spike in those arrests until people realize that the coalition is really serious," said McKiernan, adding that the "light" response to the amnesty had been "somewhat expected."

The only exemptions under the new policy will be for "coalition forces, police, security and other forces in uniform under the supervision and authority of the coalition".

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