At least four major explosions rocked central Baghdad Tuesday, as smoke rose above the fortified Green Zone. The blasts hit at 12:30 p.m. (0930GMT), reverberating through the capital. There was no immediate explanation for the explosions. The U.S. military had no immediate response. U.S. helicopters were seen circling over the area. The Green Zone, which houses the U.S. and Iraqi leadership, lies on the western bank of the Tigris River.
