Up to 500 people died when a crowd of Iraqi Shiites stampeded off a bridge over the Tigris River in Baghdad on Wednesday, fleeing rumours of a suicide bombing threat, Iraq's deputy health minister said.
"So far we have 500 dead," Jalil al-Shumari, the deputy minister, told Reuters.
The crowd, on its way to the Kadhimiya mosque for an important religious ceremony, panicked as rumours spread that a suicide bomber was preparing to blow himself up.
Earlier at least seven people died in three separate mortar attacks on the crowd.
100 bodies, one hospital
One hospital said it had received at least 100 bodies. The hospital source said bodies were being sent to two other nearby hospitals as well.
A crowd of several thousand had been marching through the old Kadhimiya district of northern Baghdad to a major Shiite religious ceremony.
The streets leading to the mosque are narrow, making it almost impossible for rescue workers to reach the dead and injured in the packed throng, and raising the possibility that the death toll could rise further, witnesses said.
Tensions have been running high between the main religious and ethnic communities in Iraq ahead of a referendum on a divisive new constitution for the post-Saddam Hussein era.
The Kadhimiya mosque is a major Shi'ite shrine in an old district of north Baghdad. The crowd was celebrating the martyrdom of Musa al-Kadhim, a revered religious figure among Shiites.
Explosions were heard across Baghdad on Wednesday morning. A Reuters correspondent reported hearing six mortar rounds exploding near the international airport, although the U.S. military had no information of any attacks there.
Parliament completed work on the draft text of the constitution Sunday, but it must be approved by a popular mandate before Oct. 15 to come into force.