Boys, some as young as six, dragged sacks of grenades to hand in to smiling American soldiers. Women in traditional Muslim abayas (black gowns) struggled with arms full of Kalashnikovs, which they duly presented to waiting troops. One man even arrived on a donkey cart lugging a rusting, but still functioning, antiaircraft gun.

The friendly co-operation might look like a new beginning for America’s troubled occupation. But it was soon apparent that the Iraqis were motivated not by a sense of civic duty, but rather out of devotion to the US dollar.

Until this week American attempts at disarming the country usually took the form of raids and searches in people’s homes, an unpopular and risky tactic. But, in one of the most successful operations conducted by the Americans to remove the huge number of weapons from civilian hands, the US military this week spent $1.2 million (£670,000) on a pilot scheme to buy back the arms at prices slightly above the black-market rate.

“The response has been phenomenal,” said Captain Kevin Baird, whose cavalry squadron was gathering more weapons than they could cope with. “We open for business at eight, but the lines start forming at six. We take the weapons off the street and inject something back into the local economy.” As he spoke, his soldiers struggled to keep up with the influx of so much weaponry. A young woman soldier with a wheelbarrow ferried rifles back and forth to a waiting truck as colleagues sorted them into those for destruction and those good enough for the Iraqi armed forces.

To one side a sapper winced as a taxi driver, whose car had just been bumping over rough ground, arrived bearing a haul of anti-tank and anti-personnel mines. They were taken away to a safe site where they joined piles of mortar shells, fuses, artillery rounds, some surface-to-surface missiles and explosives of all kind in various states of decay.

This week the Americans bought 3,200 Kalashnikov rifles, 530 rockets, 141 machineguns and 78 tank rounds. Some weapons were still in their factory wrapping paper, but others had been in several wars, including Lee Enfield rifles, dating back to the British occupation half a century ago.

“We have taken every kind of weapon from rockets to Webley pistols,” Sergeant Steven Moose from Kentucky said. “The ones we like to take off the streets are the Kalashnikovs, the RPGs (rocket-propelled grenades) and the artillery rounds, which they use for IEDs (improvised explosive devices). Those are the ones killing us.”

While the Iraqis are co-operating, they are also torn. They can get $200 for a Kalashnikov and $160 for a missile, a small fortune in Baghdad where the weapons can be bought for half that on the black market. But many refused to be interviewed or photographed, fearing that they might be seen as collaborating with the enemy.

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