U.S. troops are engaged in intense clashes on two fronts in Iraq - with Shi'ite rebels in eastern Baghdad and Sunni insurgents west of the capital in Fallujah.
More than 30 Iraqis and two U.S. soldiers have been killed in Baghdad's Sadr City district since late Monday, when militiamen loyal to radical cleric Moqtada al-Sadr attacked U.S. forces.
A third American soldier was killed today (Tuesday) in the western part of Baghdad when a patrol came under attack.
At Fallujah, a U.S. military spokesman said insurgents have attacked American positions outside the city. U.S. forces retaliated with air strikes and tank fire. Several Iraqi casualties have been reported.
In Washington, top American General Richard Myers said the enemy has become more sophisticated, causing casualties to rise.