Flames had moved quickly through the Wang Fuk Court housing estate in Tai Po district on Wednesday afternoon, spreading through the eight high-rises and transforming the densely packed complex into an inferno.

After burning for over 40 hours, the blaze was "largely extinguished" by 10:18 am (0218 GMT) Friday, the fire services said, announcing the end of its operations.

Authorities are investigating what sparked the fire, including examining the bamboo scaffolding and plastic mesh wrapped around the complex as part of a major renovation.

At the charred apartment blocks, workers searched for survivors and pulled out bodies in black bags, with an AFP reporter counting four in one 15-minute period.

Vehicles unloaded corpses at a mortuary in nearby Sha Tin, another reporter saw, with families expected to arrive in the afternoon for identification.

Many remain unaccounted for, although the exact number of missing people has not been updated since early Thursday.

On Friday, authorities said more than 50 people were still hospitalised, with 12 in critical and 28 in serious condition.

At one hospital in Sha Tin, a woman surnamed Wong was looking for her sister-in-law and her sister-in-law's twin, with no luck.

"We still cannot find them. So we are going to different hospitals to ask if they have good news," the 38-year-old told AFP in tears.

"We were already waiting at the Prince of Wales Hospital on the first day but there was no news. We also came here yesterday."

The last contact anyone had with the twins was on Wednesday afternoon, said Wong, around the time the fire was reported.

"One building went up in flames and it spread to two more blocks in less than 15 minutes," a 77-year-old eyewitness surnamed Mui told AFP.

"It was very quick. It was burning red, I shudder to think about it."

- Investigations begun -

The fire was Hong Kong's deadliest since 1948, when an explosion followed by a fire killed at least 135 people.

Lethal blazes were once a regular scourge in densely populated Hong Kong, especially in poorer neighbourhoods, but improved safety measures have made them far less common.

Hong Kong's anti-corruption body said Thursday it had launched a probe into renovation work at the complex, hours after police said they had arrested three men on suspicion of negligently leaving foam packaging at the fire site.

Residents of the estate told AFP that they did not hear any fire alarms and had to go door-to-door to alert neighbours to the danger.

Hong Kong authorities will immediately inspect all housing estates undergoing major work following the disaster, with an emphasis on shifting the sites to metal scaffolding.

Of the 94 people confirmed dead as of 6:00 am(22:00 GMT Thursday), one was a 37-year-old firefighter and two were Indonesian domestic workers.

Hong Kong's government announced a HK$300 million ($38.5 million) fund to help victims of the fire.

City authorities said they had opened nine shelters and were organising temporary accommodation and emergency funds for those who had lost their homes.

Activities around Hong Kong's legislative elections, on December 7, have been suspended.

- 'Everyone lends support' -

Some of the residents in adjacent blocks who had been evacuated as a precaution were allowed back into their homes on Thursday afternoon.

A spontaneous community effort to help firefighters and those displaced had by Friday become a well-oiled machine.

At a public square, separate supply stations for clothes, food and household goods had been set up, as well as booths providing medical and psychological care.

So much was donated that organisers put out a call on social media saying there was no need for more.

"It's truly touching," said 38-year-old Stone Ngai, one of the organisers of an impromptu aid station, on Thursday.

"The spirit of Hong Kong people is that when one is in trouble, everyone lends support... It shows that Hong Kong people are full of love."