South Koreans are demanding answers after more than 150 people were crushed to death in a stampede during Halloween celebrations in Seoul, one of the country’s worst peacetime disasters. Official mourning began on Sunday as authorities were still trying to identify all the dead, working in a makeshift morgue set up at the site. At least 22 of the dead were foreigners from about a dozen countries, while others were teenagers still too young to carry identity cards. At least one Canadian was among the dozens injured, Ottawa said. Addressing the nation on Sunday, South Korean President Yoon Suk Yeol said it was “a tragedy and disaster that should not have happened.” “My heart is heavy and it is difficult to contain my sadness,” he added, promising that the government would “thoroughly investigate the causes of the accident.” The devastation began late Saturday night, as tens of thousands of costumed revelers filled the windy, narrow streets of Seoul’s Itaewon neighborhood. Loud music blared from the bars as people danced and socialized on the street. Crowd control was limited and the police on the scene seemed to be struggling to manage the huge crowd. South Korea’s Interior and Security Minister Lee Sang-min said in a briefing that authorities did not expect Halloween crowds to be larger than previous years, despite the recent lifting of most COVID measures, and were busy with the policing of protests in other parts of the capital. By 10pm, many of the streets around the Hamilton Hotel in central Itaewon had come to a standstill and people could be heard shouting in frustration at the loud music as they tried to get through. Halloween revelers react after the riot, which killed more than 150 people. ALBERT RETIEF/AFP/Getty Images What started the deadly spree remains unclear, but some witnesses reported seeing a group of young men trying to force their way down a steep alley. One person fell and then another and panic quickly spread through the crowd. People screamed for help, but they were drowned out by other screams and the music from nearby bars. Survivors described people falling “like dominoes”, some of whom were fed up with the awkward Halloween costumes. The collapse of the strait was such that even after it became clear that something terrible was happening, many struggled to get out and paramedics had to fight their way inside, desperately performing CPR among piles of people. The majority of the dead, 97 out of 153, were young women. A female survivor, surnamed Park, told Yonhap news agency “a short person like me couldn’t even breathe,” the crowd pressure was so great. “I could have survived as I was on the side of the road,” Ms Park said. “It seems the people in the middle suffered the most.” Witness Kim Mi-sung said she performed CPR on 10 people who were unconscious, mostly women wearing witch outfits and other carnival costumes. Nine of them were found dead on the spot. “I still can’t believe what has happened,” Ms Kim told The Associated Press. “It was like hell.” For hours after the incident, bodies lay in the street, their faces covered, as paramedics struggled to register and identify the victims. By Sunday morning, the alley where the mayhem occurred had become a crime scene and a memorial, as people brought flowers and offerings for the dead. Those killed in Saturday night’s disaster include people from China, Iran, Russia, the United States, Australia, Uzbekistan, Vietnam, Kazakhstan, Austria, Sri Lanka, Thailand and Norway. Leaders from around the world expressed their condolences, with Prime Minister Justin Trudeau saying his “thoughts are with all those affected by this tragedy and we wish a speedy and full recovery to those injured.” People pay their respects near the scene of the riot.KIM HONG-JI/Reuters US President Joe Biden and First Lady Jill Biden expressed grief “with the people of the Republic of Korea”, while Chinese leader Xi Jinping also expressed “deep condolences”. Addressing worshipers in St. Peter’s Square on Sunday, Pope Francis said “we also pray … for those, especially the young, who died overnight in Seoul due to the tragic consequences of a sudden trauma.” For many South Koreans, Saturday’s disaster brought to mind the sinking of the Sewol ferry in 2014, which left nearly 300 dead. At the time, too, many of the dead were teenagers and questions were raised about safety regulations and the government’s response. In a statement, the 4.16 Foundation, founded by family members of those killed in the Sewol disaster, echoed calls for an investigation into the Halloween crash. The group urged people not to blame those “who just wanted to enjoy the festival”, adding that “the responsibility to prevent and prepare for a possible accident” rests with the authorities. “We pray that the severe wounds in mind and body that must have been inflicted on all those who had to face the terrible horror at the scene will heal as soon as possible,” he added. With reports from Reuters and the Associated Press