In a separate attack one year after the U.S.-led war on Iraq that overthrew Saddam Hussein, five American soldiers were killed when a roadside bomb was detonated beside their convoy west of Baghdad, the U.S. army said.
The Falluja violence began when two four-wheel-drive vehicles were attacked by guerrillas on a main road in the town, 32 miles west of Baghdad. A crowd then set the vehicles ablaze and hurled stones into the burning wreckage.
Television pictures showed one incinerated body being kicked and stamped on by a member of the jubilant crowd, while others dragged a blackened body down the road by its feet.
The footage showed at least three people lying dead, while some witnesses said that four were killed. It was not clear how many people were in the vehicles.
As one body lay burning on the ground, an Iraqi came and doused it with petrol, sending flames soaring. At least two bodies were tied to cars and pulled through the streets, witnesses said.
"This is the fate of all Americans who come to Falluja," said Mohammad Nafik, one of the crowd surrounding the bodies.
Some body parts were pulled off and left hanging from a pole, while two incinerated bodies were later strung from a bridge over the road and left dangling there.
It was unclear who was traveling in the vehicles, both four-wheel drives of the type used by foreign contractors, journalists, civilian members of the U.S.-led coalition and some military personnel. Witnesses said they saw anywhere between four and eight people in the cars before they were attacked.
Some of the victims were wearing civilian clothes, flak jackets and were armed, witnesses said, but that was not clear from the television footage. One of those killed had fair hair and was wearing khaki trousers and a white T-shirt.
As the victims lay burning, a crowd of around 150 men chanted "Long live Islam" and "Allahu Akbar" ("God is Greatest") while flashing victory signs.
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