Many of the casualties came when the railing of a bridge over the Tigris River collapsed in the crush, and pilgrims fell to the water below.
The tragedy occurred as several thousand Shi'a were making their way to the Kadhimiya shrine in northern Baghdad for a ceremony marking the martyrdom of Imam Musa Al-Kadhim more than 1,000 years ago.
Iraqi Interior Minister Bayan Baker Solagh labeled the stampede that killed the pilgrims a "terrorist" act. The minister said on state television that a "terrorist" was responsible for the false report of a suicide bomber that panicked thousands of pilgrims. As night fell, rescue workers were still counting bodies on the bridge and in the Tigris River.
The head of Iraq's Red Crescent Society, Said Hakki, issued an appeal for help from Iraq's neighbors. "We appeal to the people of the region, to the governments of the region, to help Iraq through this crisis. They have in the past helped Iraq: Kuwait, the United Arab Emirates, Saudi Arabia, Syria, Iraq, Turkey."
Prime Minister Ibrahim Jaafari, a member of the majority Shi'ite community, declared a three-day mourning period and
went on television to appeal for national unity.
Kamran al-Karadaghi, a spokesman for Iraqi President Jalal Talabani, told RFE/RL what is believed to have caused the tragedy: "There was panic [on the bridge]. Somebody said there was a booby-[trapped] car, and there was panic, and people fell into the river.... That's all we have. There is no other information."
It's not clear if there was a suicide bomber in the crowd, or whether that report was just a rumor.
Radio Free Iraq correspondent Nabil al-Haidari described how the fence of the bridge was broken from the pressure of masses of people. He said that tens or hundreds of them fell into the river.
Iraqi Prime Minister Ibrahim al-Ja'afari has declared three days of national mourning.Mortar Attack
Earlier, at least seven people were killed and some 40 others injured when mortar rounds exploded among the faithful near the shrine.
Witnesses say rescue workers are having difficulty reaching the dead and injured because of the throngs packing the narrow streets.
Baghdad officials say casualties are being taken to three hospitals in the city.
Radio Free Iraq correspondent al-Haidari said that movement is hindered by the security precautions in the city.
The tragedy comes amid heightened political tensions in Iraq between the main religious and ethnic communities over the country's new draft constitution.
Shi'a and Kurds support the draft, which was presented to parliament on 29 August. But Sunnis fear it will deprive them of influence and oil revenues. Sunni leaders have called for the document to be rejected in a 15 October referendum.
(With agencies) See also:
Sunnis Weigh In On Draft Constitution
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