There were reportedly 100,000 revellers in the area celebrating the first outdoor no-mask Halloween event since the pandemic. Photo: AFP
At least 149 people are understood to have been killed in a crush during Halloween celebrations in in Seoul's Itaewon district.
"The area is still chaotic so we are still trying to figure out the exact number of people injured," Moon Hyun-joo, an official at the National Fire Agency told Reuters news agency.
Local media is reporting a further 150 injured.
Foreign nationals are reported to be among the many transferred to nearby hospitals.
The deadly incident occurred on a hill where people at the top fell over, causing a massive crush.
An emergency worker assists with the transport of a victim of the deadly crush. Photo: AFP
Earlier, emergency officials said dozens were in cardiac arrest after revellers thronged Seoul's Itaewon district.
Videos from the scene show body bags on the streets, emergency workers performing CPR, and rescuers trying to pull people trapped beneath others.
South Korea's president Yoon Suk-yeol has called an emergency meeting.
In South Korea, local medical officials are likely to say only that someone is in "cardiac arrest" until there is an official announcement of death by a doctor.
Emergency workers load an injured person into an ambulance in Seoul. Photo: AFP
Crowded area 'felt unsafe'
There were reportedly 100,000 revellers in the area celebrating the first outdoor no-mask Halloween event since the pandemic.
Social media messages posted earlier in the evening show some people remarking that the Itaewon area was so crowded that it felt unsafe.
Eyewitness accounts from the area where the crush occurred suggest crowd numbers were already soaring three hours before the incident.
Raphael Rashid told the BBC he arrived in the area towards 7pm local time.
"It was very clear that there were so many people here, probably the most I've ever seen in Itaewon and the crowds were just gathering more and more.
"Toward 10pm it was clear that there were far too many people and something was unravelling at that moment.
"There are tens of thousands of people - the most I've ever seen. So many people - to the point we were being crushed on the pavement, to the point where we had to spill onto the road where there were cars.
"At that moment we could hear a lot of fire brigade, ambulances, and police trying to get through the crowd.
"No one really understood what was going on, but they were already several police cars at the scene in front of Itaewon station and police standing on top of their police cars desperately trying to tell people to leave the area as soon as possible."
The BBC's Hosu Lee, who visited the scene, said he saw "a lot of medial staff, a lot of ambulances, they were taking the bodies away one by one".
Hosu Lee said there were thousands among the crowds, and a number of bodies covered in blue sheets, alongside a "ton of police".
"A lot of young people have gathered here tonight. A lot of people came to the party and club, wearing costumes and a lot of people I've seen are distraught and sad and there are chaotic scenes," he said.
Photos and videos showed a number of both emergency responders and civilians attending to what appear to be unconscious people on the streets.
In one video numerous responders appear to be performing CPR on people in a narrow road in the district.
In another, emergency responders tried to pull out people from what appears to be a pile of people's bodies following a crowd surge.
Another local journalist said that an emergency broadcast had been sent to every mobile phone in the Yongsan District urging citizens to return home as soon as possible due to "an emergency accident near Hamilton Hotel in Itaewon".
-BBC