Partygoers have described being asked to resuscitate victims by carrying out cardiopulmonary resuscitation (CPR) on them, despite never having done it before.
    Ana, a 24-year-old from Spain, and her friend, 19-year-old Melissa from Germany, had been at a bar next to where the crush happened and were trying to leave at about 23:00 local time (14:00 GMT) when they saw ambulances coming in and police running around asking people to move to make space for bringing out the dead and injured.
    "There were so many people that they needed normal people to do CPR. So everyone started jumping in and help. We had two friends who knew how to do CPR and they went out to help," Ana told the BBC.
    "Three minutes later or maybe more, they came back, looking so traumatized and crying. Because they tried to save five or six people and they all died in my friends' hands."
    "So then I went out and I had to help two girls. I don't know how to do CPR but I was following the instructions of the people out there.
    "They were telling me how to hold their heads and open their mouths, and things like that. I was trying to help but they were both dead as well. I have to say all the people they were bringing in to do CPR, most of them were already not breathing so they couldn't do anything.
    "We couldn't do anything, that was the main trauma."
    Thousands of teenagers and adults in their 20s had descended on Itaewon in Halloween costumes, thrilled that they could finally party after two years of Covid restrictions in South Korea.
    But video clips of the disaster showed real-life horror unfolding, with one witness likening the disaster to a war movie. More than 150 died, more than 80 were injured.
    Raphael Rashid, a freelance journalist, told the BBC there were "tens of thousands of people - the most I've ever seen. So many people - to the point we were being crushed on the pavement".
    Horror as Seoul crowd crush kills more than 150
    LIVE UPDATES: Seoul crush
    The clips showed crowds jammed so tight that they could barely move; a few managing to climb out to safety; desperate bystanders helping paramedics to give CPR to victims; a long line of victims in bodybags on the pavement.
Story continues    A steeply sloping alleyway became a death trap - apparently the crowd surged forward and people at the front fell over and were trampled by those behind.
    Some video clips on Twitter show rescuers desperately tugging at people to extract them from a crowd jammed tight.
    "A short person like me could not even breathe," said a female eyewitness quoted by AFP news agency. She said she had survived as she was at the edge of the alleyway, while "people in the middle suffered the most".
    Raphael Rashid said "no one really understood what was going on" and some police were "standing on top of their police cars desperately trying to tell people to leave the area as soon as possible".
    A medic at the scene, Dr Lee Beom-suk, told local broadcaster YTN he had tried to revive a few victims with CPR, but "the number exploded soon after, outnumbering first responders at the scene". "Many bystanders came to help us with CPR."
    He said "so many victims' faces were pale". "I could not catch their pulse or breath and many of them had a bloody nose."
    Park Jung-hoon, 21, told Reuters the situation had been "completely out of control".
    And Moon Ju-young, also 21, said "there were way too many people and it was too crowded".
    "I know the policemen and rescue workers are working hard, but I would say there was a lack of preparation."
    An Itaewon resident, 53-year-old Lee Su-mi, told Reuters that "those young people who were called 'Covid generation' could finally celebrate Halloween as their first festival.
    "Then no one was able to foresee the festival turned into a disaster."
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