Two of the soldiers died on May 30, statements said, bringing that month's death toll to 121, the worst since US marines famously stormed the insurgent city of Fallujah in November 2004.

A third soldier was shot dead in Baghdad on Friday, becoming June's first casualty, according to US command.

These latest fatalities bring the number of US soldiers who have died in combat and from other causes in Iraq since the March 2003 invasion to 3,474, according to an AFP count based on Pentagon figures.

A series of mortar barrages killed eight civilians and wounded 25 others early Saturday in a Sunni neighbourhood in central Baghdad, police said, while a strategic bridge was damaged by a bomb in northern Iraq.

The mortars began slamming into the Fadhil area in Baghdad at 1:30 am. and continued sporadically until 7 am, damaging five houses, a policeman said.

Three Iraqi children died when a US tank opened fire on suspected insurgent bombers in the western city of Fallujah, the US military reported Saturday.

A tank crew observed Friday three men that appeared to be installing a roadside bomb on the side of a highway southeast of the restive city and opened fire with its main gun. The men escaped and three children were found dead.