What we know about the Hong Kong apartment fires
Hong Kong's deadliest fire in more than 60 years ripped through a high-rise public housing complex in the city's north-east this week, killing at least 128 people.
Dozens more remain missing, with 79 people confirmed injured and and 89 bodies yet to be identified.
Now, as the last flames are extinguished and the high-rise blocks smoulder against the city's urban skyline, attention has turned to the cause of the deadly fire, and the factors that allowed it to so rapidly spread.
Many Hong Kongers have described it as a "man-made disaster".
Authorities have attributed the ferocity of the blaze to Styrofoam placed outside the windows of the apartment blocks - while also noting that fire alarms in all eight housing blocks were found to be not working effectively.
Three men have been arrested on suspicion of manslaughter connected to the fire, according to local media reports, and an investigation has been launched.
What initially caused the blaze is still unclear, but here is what we do know, so far.
Where and when did the fire start?
The blaze broke out at Wang Fuk Court, a large housing complex in Hong Kong's Tai Po district, at 14:51 local time on Wednesday (06:51 GMT).
Wang Fuk Court consists of eight tower blocks, each 31 storeys high. Seven have been affected by the fire, Tai Po district councillor Mui Siu-fung told BBC Chinese. Built in 1983, the tower blocks were undergoing renovations when the fire broke out.
Tai Po is a residential district in the northern part of Hong Kong, near the city of Shenzhen on the Chinese mainland.
The complex provides 1,984 apartments for some 4,600 residents, according to a 2021 government census.
Nearly 40% of the people who lived in the Wang Fuk Court housing complex are at least 65, or older, according to the latest census.
Some of them have lived in the subsidised public housing estate since it was built.
What caused the fire?
The cause of the fire is unknown, but Hong Kong Security Chief Tang Ping-Keung on Friday attributed its rapid spread to styrofoam placed outside the windows of the apartment blocks.
A preliminary investigation previously found that the blaze had escalated unusually fast, and police had revealed that a mesh material and plastic sheets - both of which are believed to not be fireproof - was found on the outside of the buildings.
Police have arrested three men aged between 52 and 68 on suspicion of manslaughter in connection with the deadly blaze. Two of them are directors of a construction firm while the other is an engineering consultant.
A police spokesperson on Thursday said investigators were looking into the alleged actions, or failure to act, of the firm's top officials.
"We have reason to believe that those in charge at the company were grossly negligent, which led to this accident and caused the fire to spread uncontrollably, resulting in major casualties," said the spokesperson.
Authorities on Friday further noted that they had checked the fire alarms in all eight blocks and found that they were not working effectively - confirming prior reports from some residents who said they did not sound when the blaze broke out.
How serious was the fire?
This was Hong Kong's deadliest fire in at least 63 years.
Within 40 minutes of first being reported it was declared a level four alarm - but it was raised to a level five, the highest in severity, about three and a half hours later.
Local media had earlier reported that explosions could be heard inside the building and fire hoses could not easily reach the higher levels.
The ferocity of the heat had prevented firefighters from entering the buildings. Officials told reporters on Friday that even after the fire had been put out, some sections of the buildings' remained above 200C (392F).
The city's fire department on Thursday said that the combination of high temperatures, the risk of further scaffolding collapse, and the small and crowded interiors of the apartments made rescue operations difficult
Hong Kong is well-known for its tiny, densely packed inner-city dwellings, where many public rental housing tenants have an average living space of just 14.1 square metres.
It is unclear how many people were in Wang Fuk Court when the fire broke out. Hundreds were evacuated to temporary shelters, and some were allocated emergency housing units.
More than 2,311 firefighters took part in rescue operations, with 12 sustaining injuries during the response.
Authorities said 391 fire engines were also mobilised and 188 ambulances dispatched.
What do we know about the victims?
Among the dead is firefighter Ho Wai-ho, 37, who was with the service at Sha Tin Fire Station for nine years.
The fire service says it lost contact with him at 15:30 local time, and about half an hour later, found that he had collapsed. He was taken to hospital but declared dead shortly after.
"I am profoundly grieved at the loss of this dedicated and gallant fireman," said Andy Yeung, director of the fire service.
One resident, Mr Chung, told the BBC he got a panicked phone call on Wednesday afternoon from his wife saying she couldn't get out of their flat with their cat.
He rushed home from work to find the 31-storey building in flames, with black smoke billowing out of it.
Mr Chung said he and his wife kept calling each other, anxious and scared. She told him she was about to faint as the smoke got thicker and thicker.
"She probably did faint," Mr Chung told BBC Chinese on Thursday, his eyes red from tears. "I dare not call her again."
Given that hours had passed since they spoke, he was braced for the worst. "She passed away with our cat, who she loves," he said, breaking down in tears. His wife was the only one in the family who didn't go to work or school on Wednesday.
Where will evacuated residents stay?
Several emergency shelters have been set up to accommodate residents who were evacuated, the government said. The South China Morning Post reported that one of them - at Tung Cheong Street Sports Centre - was full, and residents were being directed to other shelters.
Another, the Kwong Fuk Community Hall, which is just over the road from the housing estate, was deemed unsafe. Evacuees were moved to another shelter, further away.
BBC Chinese reporter Gemini Cheng saw elderly residents, some using walking sticks or wheelchairs, arriving at some of the shelters.
At least 900 people are taking shelter in such temporary facilities, news agency AFP reports, quoting Lee.
Six schools in Tai Po will remain closed on Thursday, the Education Bureau announced, listing the affected schools on its website.
An emergency monitoring and support centre is in operation to manage the impact of the fire, security secretary Tang Ping-keung said in a statement.
A hotline for the public to ask about casualties has been set up by Hong Kong police.
What could have exacerbated the fire?
ReutersThe tower blocks at Wang Fuk Court are covered in bamboo scaffolding and green construction netting, right up to the rooftops, because they are undergoing renovations.
As mentioned earlier, authorities have attributed the quick spread of the fire to materials used in the renovation, such as mesh netting, plastic sheeting and styrofoam.
It's still unclear how the fire began, but no matter its cause, proper netting on the buildings' exterior would have been key to preventing its spread, Jason Poon, chairman of construction NGO Chinat Monitor, told news outlet Initium Media.
Substandard netting could cause the fire to spread rapidly, he added.
Another engineer told Initium Media he believes that the vast majority of mesh netting used in construction across Hong Kong is not made of fire-retardant material.
Cardboard, debris and paint thinner is also often found on the scaffolding, which along with dry weather could hasten the spread of fire, the engineer said.
One fire safety expert the BBC spoke to said the bamboo scaffolding - a common part of the city's urban landscape - also played a part in fanning the flames.
Authorities have not mentioned scaffolding as having caused or fuelled the rapid spread of the fire.
Local media reports in March said the government's development bureau had been trying to phase out the use of bamboo because of safety concerns.
The push towards using metal instead of bamboo came after a spate of scaffolding-related deaths in Hong Kong, although reports said these were caused by falls and other safety failures, rather than fires.
Professor Jiang Liming from Hong Kong Polytechnic University also noted that the blocks at Wang Fuk Court were "relatively old" - they were built in the 1980s - so "the glass windows are not that fire resilient".
"The modern buildings have double pane glass windows, but for this one they perhaps used just a single pane... [which makes it] very easy to be broken by the flames and the flames can then penetrate through the facade."
Additional reporting by Jack Lau, BBC Global China Unit and Gemini Cheng, BBC Chinese in Hong Kong.
