The exact cause of the fire is not yet known, but a criminal investigation has been launched.
A deadly inferno has torn through a massive housing complex in Hong Kong, killing at least 83 people with many more still missing, in the city's worst disaster in decades.
At least two apartment buildings are still ablaze more than a day after fires broke out, according to local media footage, with rescuers saying extremely high temperatures have hampered their ability to reach trapped residents.
A man was rescued alive from the 16th story of one of the towers in the Wang Fuk Court complex Thursday, public broadcaster RTHK reported, citing Hong Kong's fire department.
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Questions are swirling on how such a fire in a skyscraper-filled city with a usually strong public safety record and construction standards could become so deadly, leaping from building to building.
Many of the more than 4000 people who lived in the public housing estate in the city's Tai Po neighbourhood were aged 65 and over.
The exact cause of the fire is not yet known, but a criminal investigation has been launched.
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The complex was under renovation and encased in bamboo scaffolding and safety netting – a construction technique that's ubiquitous in Hong Kong and parts of mainland China. Authorities are also investigating whether flammable material, including polystyrene boards blocking windows of multiple apartments, may have contributed to the inferno.
First responders are focusing their efforts on three of the seven blocks affected, where authorities said earlier on Thursday more than 200 people were still missing.
Firefighters are planning to conduct break-in operations to gain entry to all residential units to assess if anyone remains trapped inside, the deputy director of the Hong Kong Fire Services Derek Armstrong Chan said early on Friday. These operations are set to finish by 9am local time Friday (noon today AEDT), he said.
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Chan said firefighting efforts have taken "longer than expected" because the high-rise inferno was "much worse" than first thought.
Here's what we know.
How did the blaze start?
Firefighters first received a call about the fire shortly before 3pm local time, according to the Hong Kong Fire Department.
The blaze started at Wang Cheong House, a 32-story residential building and one of eight tower blocks that make up the Wang Fuk Court complex, which was undergoing renovations, according to Chan.
By the time fire crews were on the scene at the first building, the scaffolding and netting was on fire. Firefighters began tackling that blaze, but it quickly spread from building to building, turning a single tower block fire into multiple simultaneous multi-story infernos.
At least seven of the eight tower blocks within the complex were affected by the blaze, forcing those who were able to escape the flames into temporary accommodation.
But it quickly emerged many residents remained trapped inside their apartments, with firefighters unable to reach them amid searing temperatures inside the buildings as well as falling debris.
By the early hours of Thursday morning local time, fires were extinguished in three buildings, with four still showing "scattered traces of fire," according to the city's leader, Hong Kong Chief Executive John Lee.
At a news conference on Thursday evening, Lee said that fires across all buildings were "basically under control."
It is not yet known how many of the people listed as missing were trapped and how many simply couldn't be contacted in the chaos of evacuating such a huge complex.
Firefighters knew where many people were trapped, Chan said, but the extreme heat prevented rescuers reaching them.
Evacuations, polystyrene boards
A key question for authorities remains why the other tower blocks were not evacuated more quickly once the fire began to spread from the first building.
More than 800 firefighters were deployed to tackle the blaze, with 128 fire trucks and 57 ambulances sent to the scene.
Early Thursday morning local time, a police spokesperson said Hong Kong Police arrested three men, accusing them of "gross negligence."
Police found the construction company name on inflammable polystyrene boards that firefighters found blocking some windows at the apartment complex. Officials added that they suspect other construction materials found at the apartments – including protective nets, canvas, and plastic covers – failed to meet safety standards.
"These polystyrene boards are extremely inflammable and the fire spread very rapidly," Director of Fire Services Andy Yeung said.
"Their presence was unusual so we have referred the incident to the police for further enquiries."
What do we know about the victims?
At least 83 people have been killed by the blaze so far, including a 37-year-old firefighter who sustained injuries while trying to tackle the flames, Hong Kong officials said.
Officials said the firefighter, who they identified as Ho Wai-ho, was rushed to hospital for treatment but succumbed to his injuries.
More than 100 people were injured in the blaze, including at least 18 firefighters, the city's fire department said Thursday.
Hundreds of residents are now likely homeless in a city where there is already acute shortage of housing and public housing. Lee said Thursday the city is arranging a "one social worker per household" policy to ensure that Wang Fuk Court residents get the help they need.
A 65-year-old resident of the estate who gave his surname as Ho stood behind police tape on Thursday morning and watched the smoldering tower blocks as he contemplated his next steps.
A resident of Block 1, in the easternmost corner of the complex, Ho said he fled immediately when a fire alarm sounded and counted himself lucky for the relatively light damage his building faced.
"I don't doubt many elderly, cats and dogs are still in there," he told CNN.
Is this common in Hong Kong?
This is likely the deadliest fire in Hong Kong since World War II. Previously, the 1996 Garley building fire, which killed 41 people, was widely described as the worst peacetime fire in Hong Kong history.
Disasters like this are extremely rare in Hong Kong. One of the densest cities in the world, it has a strong track record when it comes to building safety, thanks to its high-quality construction and strict enforcement of building regulations.
Also, bamboo scaffolding is ubiquitous in the city, used not only in the construction of new buildings, but also in the renovation of thousands of historic tenements every year.
But the technique has been facing mounting scrutiny for its safety and durability. While bamboo is celebrated for its flexibility, it is also combustible and prone to deterioration over time.
Hong Kong's Development Bureau recently announced that 50 per cent of new public building projects erected from March onwards would need to use metal scaffolding to "better protect workers" and align with modern construction standards in "advanced cities."
That statement drew backlash from residents, many of whom noted that bamboo scaffolding is a cultural heritage that needs to be maintained.
Pressure on Chinese and Hong Kong officials
Such a deadly blaze is likely to pile pressure on both Hong Kong and Chinese officials.
Hong Kong is a semi-autonomous part of China and run by its own local government that answers to leaders in Beijing. But China has also ramped up control over the city in recent years, especially after huge and sometimes violent democracy protests swept the city in 2019. Dissent has been quashed and protests, once a daily feature of life in Hong Kong, have been snuffed out.
Chinese leader Xi Jinping expressed his condolences to the victims of the disaster, Chinese state broadcaster CCTV reported.
Xi urged "all-out efforts" from representatives of China's Central Committee and the Hong Kong Liaison Office to do "everything possible" to assist efforts in minimising casualties and losses from the fire, according to CCTV.
Lee said that he was "saddened" by the deaths caused by the fire, expressing his "deep condolences to the families of the deceased and those who were injured."
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