YESTERDAY’S opening ceremony for a refurbished sewage plant was supposed to mark a new chapter in Amal, a dirt-poor area of southern Baghdad.

The plant was supposed to provide cleaner streets and water for thousands of desperate Iraqis. It was supposed to show how America is helping rebuild Iraq. Instead the ceremony ended with 35 children dead, gratitude turning to hatred, and an event designed to showcase the country’s reconstruction transformed into a potent symbol of its continued destruction.

As proud US officials left the plant three car bombs exploded right outside, scything down the flock of children who had gathered to beg for sweets and play football with the American soldiers standing guard. It was Iraq’s Beslan massacre — the worst slaughter of children since the fall of Saddam Hussein’s regime 18 months ago.

A total of 41 people were killed, many of them younger than ten years old. More than 130 people were wounded, at least 70 of them children.

The dead and the injured were rushed to Baghdad’s central Yarmouk hospital where hysterical parents screamed in anguish as they hurried down corridors stained with blood. In spartan wards children lay foetal and pale with pain as doctors struggled to cope with the influx of patients and bodies.

A father carried the tiny body of one dead son as he desperately searched for his other son. “Where is Akeel?” he howled as he pushed past other weeping parents.

The Americans had understandably wanted to make the most of yesterday’s ceremony. Baghdad’s sewage system was almost completely destroyed in last year’s war, leaving streets filled with raw sewage and waste pouring into the heavily polluted Tigris river.

The plant’s reopening was also a rare success story for a reconstruction programme largely stalled by sabotage and terrorism.

As US and Iraqi officials went through the formalities, US troops on the periphery played football with the children, even moving one of their patrol vehicles to make more space for a kickabout. It was a scene President Bush might have dreamed of, but then the brutal reality of Iraq kicked in.

Witnesses said the bombs went off in quick succession just after the ceremony ended at midday. And as the American Humvees pulled away, the gaggle of children were caught in the huge blasts.

Terrified parents rushed to the scene. Some witnesses said US troops and Iraqi national guardsmen, panicked by the succession of blasts, fired on the crowd, killing at least two people. Others said they thought the soldiers were trying to chase the people away for fear of further explosions. Abu Yassin, a 53-year-old local whose clothes were caked in blood, told how he ran from his house when he heard the first blast, knowing his 12-year-old son Hassan was out in the streets. He saw a barely recognisable body of his son’s age and picked it up, running to escape.

“I saw many bodies lying on the ground, some of them blown to pieces. I carried one of them, thinking it was my child, but it wasn’t mine, I could see by the clothes. The child was dead. I was crying and shouting,” he said, blank-eyed with shock. He left the small body on the ground next to two other dead children and ran about looking for Hassan.

He was later told by neighbours his son was alive and at the Yarmouk hospital, wounded by shrapnel in the leg and shoulder.

“The Americans were waving at us, laughing and playing with us,” Hassan said, lying in his hospital bed. “One of them, a private, showed us a photo of his girlfriend.”

Ten American soldiers were wounded in the blasts, two of them seriously. That was not enough, however, to convince furious fathers and uncles that the Americans themselves had not staged the massacre.

“It was the Americans who did it, because the blast happened after they left. None of them were killed,” said Mr Yassin, ignoring his son’s insistence that the vehicles were only just leaving when the first explosion hit. “They want to create and atmosphere of terrorism so they can stay here,” he said.

The uncle of another wounded boy said the Americans “want to exterminate the Iraqi people. They think Iraq will be against them for ever, and children are the future of Iraq.” But Lieutenant-Colonel James Hutton, of the US military’s 1st Cavalry Division, said: “There is no conceivable justification for attacking innocent Iraqi civilians who were attending the opening of a water pumping station.”

The network of the Jordanian terrorist Abu Musab al-Zarqawi, which is holding the Briton Kenneth Bigley, claimed responsibility for the attacks in a statement on a militant website. The claim could not be verified.

Elsewhere in Iraq yesterday, bombs exploded at a checkpoint in Abu Ghraib, on Baghdad’s western outskirts, and in the town of Tel Afar near the northern city of Mosul, where four people died in a failed assassination on a police chief.

It was a day that ended a month in which nearly 500 have died in Iraq.

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