http://news.bbc.co.uk/1/hi/world/mid...st/4199618.stm
The incident occured after bloodthirsty terrorists attacked the pilgrims with mortars and rumors of a suicide bomber began to spread.
Iraq stampede kills 'up to 1,000'
As many as 1,000 people may have died in a stampede of Shia pilgrims in northern Baghdad, Iraqi health officials have said.
The incident happened on a river bridge as about a million Shias marched to a shrine for a religious festival.
Witnesses said panic spread over rumours of suicide bombers.
Radical Sunni groups have often targeted Shias in the past, but Iraqi officials said the tragedy had nothing to do with sectarian tension.
Many victims, mostly women, children or elderly, were crushed or drowned.
MUSLIM FESTIVAL TRAGEDIES
July 1987 - Saudi security forces clash with Iranian pilgrims in the holy city of Mecca, 402 killed
July 90 - 1,426 pilgrims killed in a stampede in a tunnel leading to holy sites in Mecca
May 94 - 270 pilgrims killed in Mecca stampede
April 97 - More than 340 pilgrims killed and 1,500 injured in fires at tent city in Mina, Saudi Arabia
Feb 2004 - 251 pilgrims killed in stampede at Mina
So far, there have been at least 695 confirmed deaths.
Earlier, mortar rounds had been fired into the crowd, killing at least seven people.
About 36 others were injured when four mortar rounds landed close to the Kadhimiya mosque.
A Sunni group said it carried out the mortar attacks, according to a statement posted on a website frequently used by groups linked to al-Qaeda.
There were also reports that some of the worshippers had been poisoned.
Iraqis are preparing to vote on a proposed constitution for their country, with Shia and Sunnis sharply divided on its contents.
Wednesday is the last day the majority of Iraqis can register to vote in October's referendum.
Panic
Iraqi Defence Minister Saadun al-Dulaim said that the only people to die at the hands of insurgents were the seven killed in the mortar attack.
"What happened has nothing at all to do with any sectarian tension," he said live on Iraqi TV.
"People swarmed the bridge. There had to be a search operation at the end of the bridge, so crowds gathered and a certain scream caused chaos in the crowds and the crowds just reacted and this sorrowful incident took place."
Officials had earlier suggested that someone in the crowd deliberately triggered the stampede by saying they had seen a suicide bomber.
BBC Middle East analyst Roger Hardy says that, because of radical Sunni attacks on big Shia gatherings in the past, it was not unreasonable for the worshippers to be nervous.
Television pictures showed large crowds of Shia pilgrims heading towards the Kadhimiya mosque to mark the martyrdom of the 8th Century religious figure Imam Musa al-Kadhim.
During the crush, iron railings on the Aima bridge leading to the shrine gave way and hundreds of people fell into the water.
HAVE YOUR SAY
The hospitals are overcrowded and people are suffering
Qassim, Baghdad
The bridge links the staunchly Sunni area of Adhamiya on the east bank of the Tigris and the Shia area of Kadhimiya on the west bank.
Thousands rushed to the banks of the River Tigris to search for survivors. Young men stripped off their shirts and waded into the muddy water to retrieve bodies floating downstream.
Mourning
The incident has caused the single biggest loss of Iraqi life since the US-led invasion in 2003.
SHIA HOLY FESTIVAL
Annual commemoration of the death of Musa al-Kadhim, 7th Imam
He was successor to Prophet Muhammad, by Shia tradition
Died in Baghdad in 799 and buried at Kadhimiya mosque
As the number of dead and injured continued to rise, Baghdad's hospitals struggled to cope, with many bodies and injured people left lying in corridors and on pavements outside.
The government has declared three days of mourning.
Shia pilgrims have often been attacked by Sunni extremists seeking to trigger civil war in Iraq.