Tens of thousands of protesters marched yesterday through lower Manhattan to demand an immediate withdrawal of U.S. troops from Iraq.

Cindy Sheehan, a vociferous critic of the war whose soldier son also died in Iraq, joined in the march, as did actress Susan Sarandon and the Rev. Jesse Jackson.

"End this war, bring the troops home," read one sign lifted by marchers on the sunny afternoon, three years after the start of the war. The mother of a Marine killed two years ago in Iraq held a picture of her son.

The demonstrators stretched for about 10 blocks as they headed down Broadway. Organizers said 300,000 people marched, though a police spokesman declined to give an estimate. There were no reports of arrests.

Organizers said the march was also meant to oppose any military action against Iran, which is facing international criticism over its nuclear program. The event was organized by the group United for Peace and Justice.

The death toll in Iraq for April reached 70 yesterday, the highest for a single month in 2006. At least 2,399 U.S. military members have died since the war began. An Army soldier was the latest victim, killed yesterday in a roadside explosion in Baghdad.

That figure is well below some of the bloodiest months of the Iraq conflict, but is a sharp increase over March, when 31 were killed. January's death toll was 62 and February's 55. In December, 68 Americans died.