Firefighters in Hong Kong struggled for a second straight day on Thursday to put out a massive blaze at a high-rise housing complex, where at least 83 people have died in one of the city’s worst fires in decades.

Thick smoke continued to rise from the Wang Fuk Court complex in the Tai Po district, a crowded cluster of buildings near the mainland border. Rescuers with flashlights moved from flat to flat as parts of the towers still burned.

Authorities said it was still unclear how many people were missing. Earlier on Thursday, the city’s leader John Lee said contact had been lost with 279 residents. Officials did not provide an updated figure during a press briefing.

Video from the scene showed responders searching inside dark apartments. Orange flames were still visible through several windows, and much of the complex was blackened.

The fire began on Wednesday afternoon, spreading rapidly through bamboo scaffolding and construction netting before moving across seven of the eight towers. Officials said fires in four buildings had been extinguished, while three others were mostly under control by Thursday afternoon.

Wong Ka-wing, deputy director of fire services, said rescuers were working floor to floor in very high temperatures. “We are trying our best to find survivors and do not rule out rescuing more injured people,” he said.

More than 70 people were injured, including 11 firefighters. Around 900 residents were moved to temporary shelters.

Pope Leo XIV sent a message to Hong Kong’s bishop, expressing sorrow and offering prayers for victims, their families and emergency workers.

Many residents remained desperate for news. Lawrence Lee waited overnight at a shelter, hoping his wife would be found. “I told her to escape when the fire started, but the corridor and stairs were full of smoke. She had to go back inside,” he said.

Winter and Sandy Chung, who lived in one of the towers, said sparks flew around them as they fled. “I could not sleep all night,” said 75-year-old Winter Chung.

Three held on manslaughter suspicion

Police arrested three men, identified as directors and an engineering consultant of a construction company linked to renovation work at the complex. They are suspected of manslaughter.

Senior police superintendent Eileen Chung said investigators believed the company had shown “gross negligence.”

Officers searched the office of Prestige Construction & Engineering Company and took away boxes of documents, according to local media.

Authorities suspect that some exterior materials did not meet fire-resistance standards, allowing the blaze to spread unusually fast. Police also found highly flammable plastic foam panels fixed to windows near the elevator lobby of one tower. Security Secretary Chris Tang said further testing was underway.

Buildings covered in scaffolding

The eight-building complex, constructed in the 1980s, has nearly 2,000 units and houses about 4,800 people, including many elderly residents. It has been undergoing major renovation. Hong Kong’s anti-corruption agency has opened an inquiry into possible irregularities linked to the renovation contract.

Officials said the fire began on the external scaffolding of a 32-story block, then moved inside the building and spread to others, helped by strong winds.

Bamboo scaffolding is widely used in Hong Kong, but officials said they will review safety concerns and consider shifting to metal scaffolding.

Chief Secretary Eric Chan said bamboo is less fire-resistant than metal. “For safety, the government believes a full switch to metal scaffolding should be made where suitable,” he said.

Authorities will inspect all renovation sites across public housing estates to ensure that scaffolding and other materials meet safety rules.

This is Hong Kong’s deadliest fire in many years. In 1996, a blaze in a Kowloon commercial building killed 41 people over nearly 20 hours.