SEOUL-- Itaewon, the neighborhood where at least 151 people were killed in a Halloween crowd surge, is Seoul’s most cosmopolitan district, a place where kebab stands and BBQ joints are as big a draw as the pulsing night clubs and trendy bars.

Wedged between two of the city’s biggest parks and the War Memorial of Korea museum, Itaewon has long been popular among foreign residents and tourists thanks in large part to a major U.S. military base that was once nearby. The area's nightlife is mostly centered on one main road.

In recent years, the days around Halloween have seen Itaewon’s lively streets filled with partygoers--expat and Korean alike--dressed up in holiday costumes. Those festivities continued even during the pandemic, which temporarily dampened Itaewon’s nightlife after several cases were traced to the area’s nightclubs and other venues.

Officials believe that tens of thousands of revelers flocked to Itaewon on Saturday, in one of the biggest gatherings since the country removed most of its COVID-19 restrictions in recent months. Witnesses say the streets were so densely clogged with people and slow-moving vehicles that it was practically impossible for emergency workers and ambulances to arrive in time, leaving them helpless to prevent the situation from developing into the country’s worst disaster in years.

On Saturday night, emergency workers were seen rushing to carry the injured and dead out in stretchers as ambulances lined up in the streets and a chaotic crowd fled the area. Paramedics and pedestrians frantically performed CPR on people in the streets near rows of lifeless bodies kept under blue blankets.

Park Ji-won, who runs a Middle Eastern restaurant across the street from Hamilton Hotel, said he saw emergency workers bring out people in stretchers among the huge throngs of crowds as he closed his restaurant around 11 p.m. He had no idea what just happened.

“I just presumed a fight broke out--in my 10-plus years of doing business here, I only saw ambulances when people got assaulted or when there were fires,” Park said.

He said he was “extremely shocked” when he got home and watched the news, which was when the death toll was at a dozen. “But then the death toll kept growing until it became 151,” he said.

Park said Itaewon always had large Halloween crowds, even during raging COVID-19 infections last year. He said shop owners like him usually avoid the narrow alley beside Hamilton Hotel during holiday festivities, because “once you go there, you cannot move or get out.”

For some people, it was the contrast between the normally lively, fun neighborhood and the mass death that was most striking.

“People were wearing Halloween costumes so the scene was so unrealistic,” said an official at an Itaewon tourism organization who rushed to the scene to try to help. She requested anonymity because of the sensitive nature of the incident.

While there's not widespread Western-style trick-or-treat activities in South Korea, Halloween-themed parties and events have become increasingly popular among young South Koreans, and Itaewon is the country’s hottest spot for such events, where bars, clubs and restaurants hold costume competitions.

Itaewon’s international character was shaped by its proximity to a U.S. military garrison nearby. The area is still home to restaurants, bars and other businesses catering to the American community in Seoul.

The Yongsan Garrison, which served as the headquarters for the U.S. Forces Korea and the United Nations Command until 2017, is less than a mile away from Itaewon. The U.S. forces have since relocated their South Korean headquarters to Pyeongtaek, a city 70 kilometers south of Seoul, leaving only a small contingent in Yongsan while beginning to hand over the land to the South Korean government.

Even after losing most of its American military customers, Itaewon has remained a major attraction for both South Koreans and foreign visitors, who are drawn to the district’s buzzing and boozy nightlife as well as its international flair. Restaurants serving American barbecue and Middle Eastern kebabs sit alongside Irish pubs and traditional Japanese-style bars.

“The Itaewon community has opened its arms to us for many years and is part of the reason our Alliance is so strong,” U.S. Forces Korea, which commands the nearly 30,000 American military personnel in the country, said in an online statement, written in English and Korean. “During this time of grief, we will be there for you just as you have been there for us.”

The epicenter of the disaster appeared to be on a cramped, sloping alley running along the western side of the Hamilton Hotel, where some witnesses say people fell and toppled over one another like “dominoes.” The brick hotel and its adjacent shopping center are a well-known landmark in the area.

The lane would have left those seeking shelter with few options. One side is occupied by the mostly solid wall of the hotel. The other is lined with a handful of small storefronts, including bars, a small retail shop and a branch of the Emart24 convenience store chain.

The alley itself is on an incline that leads to one of the entrances to the busy Itaewon subway station, making it harder for revelers to maintain their footing as the crowd surged. The block-long alley links the main road with another narrow strip packed with bars and trendy restaurants.

One witness told local TV station YTN that he saw both foreigners and Koreans who'd been killed and seemed amazed as the neighborhood filled with police vehicles and ambulances trying to help the injured and dying.

“It was like an abyss,” the man, who gave his name as Hwang Min-hyuk, said.