Twenty-four Iraqi children were killed Wednesday by a suicide car bomber targetting US soldiers as they handed out chocolates in a Baghdad neighbourhood they had entered to warn of a possible attack.
Some 20 more children were wounded in the blast, while a US soldier died and three were injured, hospital and US sources said.
"Children gathered round the Americans who were handing out sweets. Suddenly a suicide car bomber drove round from a side street and blew himself up," Sergeant David Abrams said.
A nearby house was set ablaze by the explosion.
Witness Mohammed Ali Hamza said US forces had gone to the southeastern district of Al-Jedidah to warn residents to stay indoors because of reports of a car bomb in the area.
At the nearby Kindi hospital, hundreds of distraught parents mingled in blood-soaked hallways shouting and screaming as they looked for their children, many of whom were badly mutilated.
"We have received the bodies of 24 children aged between 10 and 13," said the official in charge of the morgue.
Abu Hamed whose 12-year-old son Mohammed was killed, said: "I was at home. I heard the explosion. I rushed outside to find my son. I only found his bicycle."
He found his son in the hospital morgue.
"I recognized him from his head. The rest of the body was completely burnt."
Among the young bodies at the morgue, some headless or missing limbs, two children still clutched blue chocolate wrappers.
Hassan Mohammed, whose 13-year-old son Alaa also died, swore at insurgents for attacking civilians.
"Why do they attack our children? They just destroyed one US Humvee, but they killed dozens of our children," he said as women screamed, slapped their faces and beat themselves over the head.
"What sort of a resistance is this? It's a crime," he added.
The last such attack involved a triple car bombing against US troops inaugurating a water treatment plant in western Baghdad on September 30. Forty-three people were killed, including 37 children who had gathered to take candy from the soldiers.
Meanwhile, a Sunni Muslim religious official said the tortured bodies of 11 Sunni Arabs, who were killed execution-style with a bullet to the head, were found in Baghdad Tuesday. The men, who were accused of aiding the insurgents, were arrested by police commandos two days earlier, he added.
The Sunnis, including an imam prayer leader, were arrested in a police commando raid at their homes in northern Baghdad early Sunday, said the official of the Waqf religious organisation who did not want to be identified.
Their bodies were found dumped in the north of the city, he added and "all bore torture marks and bullet wounds to the back of the head."
Hussein Ali Kamal, deputy minister for intelligence at the interior ministry, said it was not known who was responsible for the killings.
"The minister has issued orders that nobody be arrested without a warrant," he said.
"Every day we find innocent people killed and their bodies dumped in the streets. We don't know who's responsible. The minister has ordered that a special committee be set up to look into this very explosive issue.
"There are people who dress up in police or commandos uniforms to carry out, even at night, horrible attacks which are then blamed on police," he said.
The head of the Waqf, Adnan al-Dulaimi, called Wednesday for an official investigation into the case and asked that its results be made public.
"This isn't the first time this sort of thing has happened," Dulaimi said in a statement. "We want to know who is responsible for such horrible crimes."
There have been numerous allegations of mistreatment and killings of Sunnis by special police forces over the past few months.
Sunni Arabs, dominant under the regime of ousted dictator Saddam Hussein, are believed to provide the backbone to the current insurgency.
The latest twist in growing tensions between Sunnis and the majority Shiite community came amid reports of another suicide attack, this time against a Sunni mosque near the Iranian border.
Two died and 16 were wounded as the bomber blew himself up Tuesday evening as the faithful were leaving the in Jalawlah, after evening prayers, police said.
In other incidents Wednesday, two police were killed and six people wounded, including three police, in a series of attacks in and north of the capital.
Two Iraqi soldiers were also killed by insurgents north of the capital, one by a suicide bomber who drove a motorcycle at a military convoy.
Two Iraqi civilians also died, one in crossfire as insurgents attacked an army checkpoint in Tuz, north of the capital, the other when mortar fire struck a US base he was working at, 200 kilometres (120 miles) north of Baghdad, police said.
In Washington, the chairman of the joint chiefs of staff, General Richard Myers, said Tuesday a key aide to Abu Musab al-Zarqawi, the leading Al-Qaeda operative in Iraq and a fanatic anti-Shiite, has been captured by US forces.
But he acknowledged that coalition troops in Iraq faced "a very dangerous insurgency" that is far from being on its death bed.
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