Brig. Gen. Mark Kimmitt, the chief U.S. military spokesman in Iraq, said he was unaware of the damage to the shrine, but said: ''I can just tell you by the looks of where we were firing and where Muqtada's militia was firing, I would put my money that Muqtada caused it.''

Reports of the damage to the shrine, which includes the tomb of the son-in-law of the prophet Muhammad, Imam Ali, were widely reported across the Middle East by Arabic language television stations.