US forces sustain worst casualties of war

US forces have sustained their worst casualties of the war in two bloody battles near Nasiriyah.

The battles drew some attention from the rapidly advancing ground force, which is now less than 100 miles from Baghdad.

Outside Najaf, at the northern end of the advance, there have been pre-dawn skirmishes with Iraqi fighters.

Meanwhile scores of American military personnel have landed in Kurdish territory, as the move to open a northern front gathers strength.

"I think we are advancing more rapidly than anyone could have expected," said US Major General Daniel Leaf, who co-ordinates the coalition's air campaign.

But at Nasiriyah - 230 miles south-east of Baghdad - the Allies sustained their worst casualties so far.

American authorities said two bloody battles on Sunday came after marines came under attack from an Iraqi force that had appeared to be surrendering.