NAJAF, Iraq (Reuters) – Thousands of mourners poured into the holy city of Najaf on Thursday to bury some of the victims of the stampede in Baghdad in the burial ground most sacred to Iraq”s Shi”ite Muslims.

The stampede on a bridge over the river Tigris during a religious festival on Wednesday killed around 1,000 people, the greatest loss of Iraqi life in a single incident since the U.S. invasion of 2003.

The government announced a full judicial inquiry.

Hundreds of graves were dug at a cemetery in Najaf, 160 km (100 miles) south of Baghdad. This Reuters correspondent saw at least 130 bodies being buried, with other graves open.

Every few minutes, empty coffins left the cemetery to return with more bodies.

Ali Karim Jabbar was on the bridge with his brothers, Rahim, 30, and Rashed, 25, when the stampede started. Both died and were buried at Najaf.

&#34Everyone was crossing the bridge; it was suddenly closed and then someone shouted there was a suicide bomber,&#34 he told Reuters, weeping. &#34The crowd in the front tried to go back and the people in the back tried to push them to the front.&#34

&#34When this happened there was a stampede, my two brothers disappeared. After it calmed down we found one of them crushed to death and the other in the hospital this morning — dead.&#34

At least 965 people have been confirmed dead after thousands of Shi”ite pilgrims got caught in the crush and died when they jumped into the river below or were suffocated on the roadway.

It was not clear whether the alert about the bomber was by evil design or simple panic.

Ahmad Yasser, 22, who had a leg amputated after being hit by shrapnel from a U.S. helicopter missile in February in the poor Sadr City Shi”ite region of Baghdad, had a lucky escape.

&#34I was with friends, there was a stampede and I found myself on the ground with people trampling over me,&#34 he said.

&#34I struggled to breathe when my friends threw me into the river, I can”t remember being in the air but I remember the river police taking me out.&#34

Earlier, at Baghdad Medical City, a hospital in the capital, frantic relatives searched bodies swathed in bright red and yellow blankets looking for loved ones, many holding their noses against the stench as the searing summer heat hastened decomposition.

The road to Najaf was choked with coffins loaded onto minivans and coaches. Security was stepped up, with dozens of police and army checkpoints on the road.

The final death toll, one senior official said, was likely to be more than 1,000, once all the bodies in hospitals, makeshift morgues and family homes across the city were counted.

Prime Minister Ibrahim Jaafari on Thursday ordered the payment of 3 million dinars (around $2,000) to the family of each victim of the disaster.

Though fears of sectarian attacks, real or imagined, may have contributed to the panic that drove the pilgrims to their deaths, the shock was felt across the factional divides.

A barrage of rocket attacks on the crowd, some 200,000 strong or more, had sparked tension early in the day. It killed seven and was claimed by a Sunni group avowing links to the insurgency against the U.S.-backed, Shi”ite-led government.

Jaafari, apparently accepting that the stampede was inspired by Sunni radicals, vowed tough action against them.

&#34The coming period will witness a strategic development in confronting terror and terrorists. And we will hit hard those murderers, radical militants and Saddamists,&#34 he said.

Yet his spokesman, Laith Kubba, later said simply, &#34Chaos was behind this,&#34 and said officials should not jump to conclusions. He praised residents of the Sunni neighborhood across the river for saving many from drowning and the mosques of the militant Sunni stronghold of Falluja for offering aid.

&#34I hope this incident will have a positive effect on us,&#34 he said. &#34Let us forget the little things. There should be real cohesion among the people of Iraq and this can be achieved.&#34

Wednesday”s disaster was by far the biggest loss of life in such a crowd since more than 1,400 pilgrims died at Mecca during the haj in 1990.

Whatever sparked the rush for safety, the fear that a bomber might be on the loose was well grounded after previous attacks on Shi”ite religious events in the past two years.

Tensions are high among Iraq”s rival religious and ethnic communities ahead of a referendum on a new constitution for the post-Saddam Hussein era.

But despite the pall of death hanging over the country, government spokesman Kubba said Iraq hanged three criminals on Thursday, the first executions since the fall of Saddam.