Tai Po, Hong Kong: There was no alarm, nothing to alert the residents to the tragedy fast unfurling across their Hong Kong apartment complex on a Wednesday afternoon.

Wing Wu smelled the smoke first. It drifted through the corridors and then billowed under doorways. Then came the cries of “fire!” and people banging on doors, screaming for people to leave.

When he opened his door, orange flames leapt at him from his neighbour’s apartment across the hallway.

“We knew we had to go right then,” says Wu, 41.

“Without the alarm, I was not aware of the seriousness of the fire, and then people started yelling.

“The fire was pretty small at the beginning. The flames grew higher and higher, and it spread quickly.”

Wu and his wife, Karen, were the lucky ones. Their apartment was on the fifth floor of Block E in the Wang Fuk Court complex in Hong Kong’s northern Tai Po neighbourhood – low enough for them to make a quick escape down the stairs.

By morning, seven of the eight towers in the complex were blackened, burnt-out shells, with fires still roaring inside three of them.

At least 83 people were dead and about 300 were missing in what was Hong Kong’s deadliest fire in decades. More than 70 people were injured, including 11 firefighters, the Fire Services Department said.

As rescue efforts turn to recovery, the city is bracing for the death toll to climb much higher.

Dozens of fire trucks crowded the streets surrounding the complex, and ladders extended high into the sky, allowing water cannons to blast the upper floors of the 32-storey buildings.

Singed green mesh hung like threadbare drapes across bamboo scaffolding that had been erected around the towers for renovations.

Police arrested three people connected to the construction company as authorities expressed suspicion that the mesh and foam used in the renovations contributed to the fire’s rapid spread.

On the ground below, Hongkongers filled the streets, silently filming the catastrophe on their phones. The astringent smell of burning metal filled the air.

Speculation quickly swept across Hong Kong about the possible cause of the fire. Unverified reports circulated among residents and onto social media about construction workers smoking on site, near the scaffolding.

The city quickly rallied. Volunteers carrying food and water arrived at the fire site. Makeshift shelters sprang up at schools, churches and community halls, heaving under the weight of donated clothes and goods, as authorities scrambled to accommodate many of the 4600 people who lived in the towers.

Outside an evacuation centre close to the towers, shell-shocked residents wandered around aimlessly. Their homes destroyed, their belongings incinerated, their neighbours missing, they had nowhere to go. One woman sat in the gutter, crying.

As authorities began the process of contacting relatives to identify loved ones, pain rippled across the neighbourhood. Another woman, so distraught she was unable to walk, was carried out from a community centre by rescue workers.

Amidst the devastation, a splinter of joy. An elderly man had been rescued alive from the 31st floor of one of the towers.

Elsewhere, Mr Si, 72, had been at a doctor’s appointment when the fire broke out on Wednesday.

He returned to find his home on the 19th floor in Block A on fire. Many of his neighbours are missing.

“There was no alarm. A lot of elderly people would have died because they did not hear an alarm,” he said, tears streaming down his face.

“Everything is gone,” he says.

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