All nine of the soldiers and marines were killed on Tuesday in a series of incidents, some of them in an area where the troops were searching for three of their comrades who were captured 11 days ago.

Three soldiers were killed when their patrol was hit by a roadside bomb attack south of Baghdad, one was shot dead in the capital and another hit by a booby trap as his unit operated near where the men went missing.

Two more soldiers were killed by another roadside bomb north of Baghdad, while two marines died in action in the restive western province of Anbar, according to statements from US command in Baghdad.

Since the March 2003 US-led invasion, 3,433 US troops have died according to an AFP count based on Pentagon figures.

Iraqi police yesterday found what they believed was the body of an American soldier floating in the Euphrates river south of Baghdad ,11 days after three US troops were snatched by al-Qaeda.

Thousands of US troops were scouring orchards and waterways south of Baghdad for the three missing soldiers captured by al-Qaeda militants in a pre-dawn ambush on May 12 that killed four US soldiers and an Iraqi interpreter.

"We found the body of a man wearing a US military uniform with a tattoo on his right arm," said Captain Muthanna Hassan of the police in Mussayib, which is a short distance from the town of Mahmudiyah, the epicentre of the search.

The US military later confirmed it had received the body.

"Iraqi police did find the body of a man whom they believe to be one of our missing soldiers," spokesman Major General William Caldwell told reporters.

"We have received the body and we will work diligently to determine if he is one of our missing soldiers, but we have not made any identification yet.

Meanwhile, at least 20 people were killed when a suicide bomber blew himself up yesterday in a crowded cafe in a predominantly Kurdish town near the Iranian border, police said.

"There were 20 killed and 15 wounded as well, all of them men. A suicide attacker blew himself up in a cafe in Mandali," said Lieutenant Ahmed Ali of the Iraqi police force in Diyala province, north of Baghdad.

The blast came five days after alleged Al-Qaeda gunmen massacred 16 Kurdish villagers in a community just outside Mandali, which lies 100 kilometres northeast of Baghdad near the Iranian border.

Diyala is in the grip of a vicious three-way conflict between Sunni insurgents, Shiite militias and allied US and Iraqi security forces.

Many of the Kurds of Mandali are Shiites, and there have been unconfirmed reports that Al-Qaeda is trying to drive them from the border area in order to secure a smuggling route from Iran.