The marines were on a foot patrol outside Fallujah, just west of Baghdad, when they were attacked, according to a statement from the US Military.
The patrol was attacked with an improvised explosive device fashioned from several large artillery shells.
The dead were from the 2nd Marine Division’s Regimental Combat Team 8.
White House reaction
The White House said that President George W. Bush was saddened by the death of the 10 US marines.
“We are saddened by the loss of lives, whether it is one soldier who loses
his or her life or 10 or 11,” said spokesman Scott McClellan.
“Our hearts and prayers go out to the families, their loved ones. We are
forever grateful for their service and sacrifice,” the spokesman added.
The attack was the deadliest on US forces in Iraq since an August 3 blast killed 14 marines during combat operations near Haditha, 260 km north-west of Baghdad.
More than 2,110 US service personnel have died in Iraq since the March 2003 invasion.
News of the latest attack came as about 500 US and Iraqi troops launched a new offensive against insurgents in Ramadi, also west of Baghdad.
The offensive came a day after Ramadi residents reported a sudden insurgent presence on the streets, with dozens of fighters roaming unchecked and putting up al-Qaeda posters.
Meanwhile the kidnappers of four Western hostages in Iraq have threatened to kill them unless all detainees in Iraqi and coalition prisons are released by December 8, Al-Jazeera television reported.
The threat was made in a video purportedly from the self-declared Brigades of the Swords of Right, which claimed to have seized an American, a Briton and two Canadians working for a group called the Christian Peace Team.
It gave those it called “the people concerned with abductees affairs” until
next Thursday to meet its demands or said it would kill the four.
The statement was accompanied by a video showing the two Canadian hostages being offered food.
They and the British hostage were also shown calling for an end to the US
and British military presence in Iraq.