Roadside bomb kills 3 U.S. soldiers in Iraq

BAGHDAD (Reuters) - Three U.S. soldiers were killed by a roadside bomb on the outskirts of Baghdad on Tuesday and one more was wounded, the U.S. military said.

It also announced the death of another U.S. soldier, killed on Monday by a roadside bomb near Diwaniya, 180 km (110 miles) south of Baghdad. Two more soldiers were wounded by the bomb.

President Bush is sending 21,500 extra troops to Iraq, most to Baghdad to join a major new security crackdown aimed at stemming sectarian bloodshed in the capital.

U.S. troops and Iraqi forces have stepped up their presence in and around Baghdad as part of the plan.

A U.S. statement said the soldiers killed on Tuesday were conducting a "route clearance mission" southwest of the capital.