A devastating fire has ripped through several high-rise tower blocks in Hong Kong, killing at least 44 people, making it the deadliest in more than 60 years. More than 270 have been reported missing and thousands of residents are in evacuation shelters.

Pictures show several buildings ablaze, and thick smoke billowing into the air, dominating the Chinese territory's skyline.

As night fell, the fire was still burning hours after it was first reported, with more than 760 firefighters deployed to the scene. Three men have since been arrested on suspicion of manslaughter connected to the fire, according to local media reports, and an investigation has been launched.

Chinese President Xi Jinping has expressed condolences to victims, including a firefighter who died in the line of duty, state media report. What caused the blaze is still unclear, but here is what we do know, so far.

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 stories high. Seven have been affected by the fire, Tai Po district councillor Mui Siu-fung told BBC Chinese.

They provide 1,984 apartments for some 4,600 residents, according to the 2021 government census. Built in 1983, the tower blocks were undergoing renovations, and the outside of the buildings was covered in bamboo scaffolding and construction netting. Footage shows the fire spreading quickly through the bamboo.

There have been reports by residents in some local media that fire alarms did not sound. A preliminary investigation found that the rapid spread of the fire was unusual, Hong Kong's security secretary said early on Thursday morning. One of the factors in this was said to be the use of polystyrene - which can be highly flammable - around windows.

The Hong Kong fire department has classified the blaze as a level five alarm - the highest in severity. Local media reported that explosions could be heard inside the building, and fire hoses could not easily reach the higher levels. The ferocity of the heat was preventing firefighters from entering the buildings to conduct rescue operations.

The death toll increased significantly early on Thursday morning, with officials reporting that the tally had risen to 40, and 45 people were in critical condition in the hospital. Among the dead is firefighter Ho Wai-ho, who lost his life during the rescue efforts.

In the wake of the tragedy, emergency hotlines and shelters have been established for evacuees and those searching for missing loved ones. The authorities have arrested three men, ages 52 to 68, suspected of manslaughter in connection to the incident. Authorities are investigating possible negligence in the lead-up to the disaster.

The incident raises serious questions about the ongoing use of bamboo scaffolding in construction, a practice that has drawn increased scrutiny for its inherent safety risks. As the community grapples with the losses, the investigation continues to uncover the factors that led to this devastating fire.