An Iraqi man celebrates atop of a burning U.S. Army Humvee in the northern part of Baghdad, Iraq, Monday, April 26, 2004. An explosion leveled a building in northern Baghdad on Monday, setting four U.S. Humvees nearby on fire. At least one U.S. soldier and several Iraqis were wounded. The cause of the explosion was not immediately known. (AP Photo/Muhammed Muheisen)