Hong Kong’s deadliest fire in seven decades has claimed 55 lives, prompting the city’s leader to order territory-wide inspections of public housing estates undergoing renovations, as criminal investigations widen into possible graft and safety breaches.

The massive blaze swept through Wang Fuk Court in Tai Po on Wednesday afternoon, quickly engulfing seven out of eight residential blocks wrapped in bamboo scaffolding and green mesh as part of renovation work that began in July 2024.

Officials said 51 victims were found dead at the scene, while a firefighter later succumbed to injuries. As of Thursday morning, 68 people are hospitalised, including 16 in critical and 25 in serious condition. Rescue teams say around 280 residents remain unaccounted for, with flames still active on the upper floors of three 31-storey blocks.

Authorities described the rapid spread of the fire as “unusual”, revealing that highly flammable styrofoam was found sealing lift windows on every floor, allowing flames to race through corridors and into flats. Investigators also found that external scaffolding nets and sheeting failed to meet fire safety standards.

The government has launched full-scale criminal probes into the cause of the inferno. Police on Thursday arrested three people — two directors and a consultant of the contractor responsible for the renovation — on charges of manslaughter for allegedly using non-compliant materials. Officers are also searching the offices of the housing estate’s management company.

The fire, first reported at 2:51pm, escalated from a No. 1 alarm to the city’s highest No. 5 alarm by 6:22pm, sending thick columns of smoke into the sky, with dramatic footage showing bamboo scaffolding erupting into towering pillars of flames.

Hong Kong Chief Executive John Lee Ka-chiu visited the injured on Thursday, pledging a full investigation into the fire and renovation practices. He also suspended all election campaigning ahead of the December 7 Legco polls, saying authorities may review whether the election needs to be postponed.

The death toll of 55 has now surpassed the 1996 Garley Building fire that killed 41, making it the city’s worst blaze in nearly 70 years.