The Eighth Brigade of the 2nd National Police Battalion, which has more than 800 uniformed officers in western Baghdad, was stepped down a day after armed men in official uniforms herded off 14 shopkeepers from central Baghdad, and two days after 24 workers were abducted from a meat processing plant in the capital.

“The brigade’s past performance does not demonstrate the level of professionalism sought by the Ministry of the Interior,” Major General William Caldwell said. “It was realised that removing them would, in fact, enhance security.

“There was clear evidence that there was some complicity in allowing death squad elements to move freely, when in fact they were supposed to be impeding their movement.

“The forces in the unit have not put their full allegiance to the Government of Iraq and gave their allegiance to others.”

Sunni leaders have for months accused police units of helping Shia death squads to carry out a series of massive kidnappings, which have included the abduction of the entire US-Iraqi Chamber of Commerce, several groups of factory workers and the whole of the Iraqi Olympic Committee. They have charged that the police forces are infiltrated by members of Shia militias who have killed scores of innocent people.

Brigadier Abdel Karim Khalaf, an Interior Ministry spokesman, said the lieutenant-colonel in charge of the Eighth Brigade had been detained and was being questioned, while rank-and-file policemen were being investigated at random.

The charges of complicity in the sectarian war that has crippled the capital was a further admission by the Shia-led Government that its own security forces are partly responsible for the incessant violence.

Nouri al-Maliki, the Prime Minister, announced on Tuesday a four-point plan that included the establishment of neighbourhood committees, which would be able to report on suspicious activities by the security forces and local militias.

The disgraced brigade will be sent for retraining by American forces, although one US trainer said the programme had been scheduled months ago as part of a sweeping overhaul of Iraq’s police forces, which were hastily recruited after the 2003 invasion and which have frequently proved inadequate for the task of eradicating violence.

In late 2004 almost the entire police force in Mosul fled their bases when insurgents attacked, while Shia policemen in Najaf joined rebels from the al-Mahdi Army and gave them their weapons when they took over the shrine city that year.

Since those big setbacks, US forces have been retraining the police, but the programme has had little impact.

A survivor of Monday’s mass kidnapping in a parade of computer shops near the Technology University described how half a dozen vehicles, with official security forces markings pulled up and men in military fatigues rounded up all the Sunnis. They drove off with 14 people but stopped two shops short of his establishment, he said.

The bodies of several of those abducted from a meat processing plant on Sunday were dumped on the streets, showing signs of torture. Hundreds of Sunni residents demonstrated near the factory carrying banners saying “Get police troops out of our area”.

An American official involved in the police training programme said the Eighth Brigade had been scheduled for retraining for months, and insisted that not all its members were under suspicion. “It’s totally ridiculous that we’d take somebody who’d just been arrested and send them for training again,” he said.

Iraqi police have long been the target of al-Qaeda suicide bombers and attackers, who view them as agents of a US- installed Government. Thousands have been mown down at recruiting centres or ambushed on patrol or in their bases. Despite the dangers, many young men still want to join the force in a country whose economy is in ruins and where the regular income often outweighs the dangers of the job.

The force of around 100,000 is divided into various branches of local and national police, with battalions of special police commandos attached to the Interior Ministry. But the division within the forces is blamed by many for the impunity with which they act, with one group often not knowing what the other is doing.

$20m fund for victory party

A $20 million allowance has been set aside for a "victory in Iraq" party in Washington. The fund, to pay for a celebration "for commemoration of success" in Iraq and Afghanistan, had been tucked away in fine print of the 2006 budget. Although it has not been spent, Senetors have apparently rolled it over into the spending Bill for 2007.

The Pentagon said it did not know who had put the fund into the budget, but admitted that it looked "a bit premature".

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