SEOUL, Oct 30 — For hours, they pulled body after body out of the crushed tangles of limbs that filled the narrow Itaewon alleyway at the epicentre of South Korea's worst ever stampede. But it was often too late.

Three off-duty American soldiers stationed in South Korea told AFP how they found themselves caught up in the crowd surge and crush that killed 151 people and injured scores more, describing scenes of chaos, suffering and death as they struggled to help.

An estimated 100,000 people attended the event, which local vendors said was "unprecedented", but the overstretched police force, also dealing with a protest across town, only planned to deploy some 200 officers.

The three US soldiers told AFP they were part of the crowd coming down the narrow, steep alleyway that became a death trap, but they were able to escape onto a ledge-like area at the side.

But just after they managed to leap out of the crowd "it started happening — everybody just fell on top of each other like dominoes," Jarmil Taylor, 40, told AFP.

People at the top of the alleyway were trying to force their way down, even though the street was already rammed full — and then people began to fall.

"There were people on top of people — it was layers of people. They didn't have enough people there to help them at once," Taylor, visibly dazed and tired, told AFP Sunday at the scene.

"People in the pile were panicking which made the situation worse. There were sounds everywhere that made it impossible — screaming people just drowned out all the sounds," he added.

He and his friends would try to pull victims out of the crush and carry them to safety so that emergency responders could perform CPR, he said.

"We were picking a lot of people and taking them into the nearby clubs since they had finally opened them up. The clubs' floors was filled with people laid on the ground."

'It just fell apart'

Washington stations some 27,000 US troops in South Korea to help protect it against the nuclear-armed North, and Taylor and his friends are based at Camp Casey in Gyeonggi.

On their week off, they decided to go to the festivities at Itaewon, but said that when they found themselves in the huge crowd, they realised something was wrong.

"We were getting nervous too, we were in the middle of it and that's why we got off to the side, and that's when it just fell apart," said Dane Beathard, 32.

People were crushed so tightly into the alleyway that emergency workers could not get them out of the packed crowd, he said.

"We helped pull people out all night ... It was a long time for people stuck in there not to breathe," Beathard said.

"All of the people crushed were in the front, where they collapsed into a pile," he said, adding that at the worst points it was "a fifteen foot layer of people".

Authorities said the majority of victims were young women in their 20s.

"There were a lot of women in the crowd who got crushed," said Jerome Augusta, 34.

"I think because they were smaller their diaphragms were crushed. And because they were panicking, which made it more chaotic," he said.

Initially there were barely any police or emergency responders at the scene, the trio said, and the scale of the crowd meant that the people at the back had no idea that disaster was unfurling right in front of them.

"We were screaming at them to back up, but it was too little too late," Augusta said.

The soldiers stayed on the edge of the crush all night, desperately trying to pull people out of the piles of bodies, but said that by the time they got to them, it was often too late.

"We are not small guys but we were crushed too before we got out," Taylor said, adding that the disaster had struck so quickly they had not managed to process what was going on.

"What you've got to understand is the people stuck in the front they were all on the ground — crushed. So you couldn't push forward and trample everyone in front, so people piled up as they fell," he said.

The trio said they felt lucky to have survived.

"When we left there were bodies everywhere, everywhere," the three of them told AFP. — AFP