Multiple explosions tore through crowds of Shi'ite worshipers outside two major Shiite shrines in in Baghdad and the holy city of Karbala. News reports say at least 100 people were killed and many others were injured. Correspondent Laurie Kassman has more from Baghdad.
Ambulances rushed to the shrine in Baghdad as religious clerics called for calm over loudspeakers and appealed for blood donations for the injured.
Saad al-Kabi, 38, still shaking from the shock, says he was walking toward the mosque to pray just before 10 in the morning when an explosion ripped through a crowd of women in front of the shrine. It was so awful, he said, with body parts and blood everywhere.
Four explosions rocked the major Shi'ite shrine in Baghdad as pilgrims gathered at the shrine there to celebrate the last day of the Shura holiday.
As relief workers and volunteers evacuated the injured in Baghdad, groups of worshippers began marching in the street in front of the shrine chanting, "We are not afraid of death."
At least five bombs ripped through crowds of worships outside the holy Shi'ite shrine in Karbala, about 100 kilometers south of the Iraqi capital.
Some enraged survivors blamed foreign militants for the attacks. Others threatened revenge against Sunni Iraqis. Some worshippers, still in a state of shock after the morning explosion voiced concerns it would fuel sectarian tensions. Angry mobs briefly lobbed stones at U.S. soldiers and Iraqi police who rushed to the scene.
A U.S. military spokesman has condemned the attacks in Baghdad and Karbala and says the blasts may have been caused by both mortar attacks and suicide bombings. Nobody has claimed responsibility for the attacks.
Last month, U.S. forces said they had intercepted a message by a suspected al-Qaida terrorist urging suicide bombings against Shi'ite Iraqis to provoke civil war.
This was the first time in three decades that Shi'ite Iraqis could openly celebrate the Shura holiday, one of the most important religious periods in Shi'ite Islam. Saddam Hussein had banned Shi'ite Muslims from public displays of worship.
Thousands of Iranian Shi'ite pilgrims had also flocked to the shrines to commemorate the death of the Prophet Mohammed's grandson who was slain in battle not far from Karbala 1,300 years ago.
After years of persecution under Saddam Hussein, Iraq's Shi'ite leaders have demanded guarantees for their religious rights in any future government. Some clerics have called for Islamic law to be implemented. The Iraqi Governing Council this week approved an interim constitution that makes Islam one source but not the sole source of legislation, with a bill of rights safeguarding the basic rights of all Iraqis.