The BBC is reporting that six people have been confirmed dead in the fire that ripped through 24-storey London apartment building Grenfell Tower.

The fire began just before 1am local time and quickly spread through every floor above the ground floor, with “several hundred” people estimated to have been inside when the fire started, most of them asleep.

Over 70 people have been taken to hospital, with at least 20 reportedly to be in a critical condition. At time of writing, firefighters are still working to combat the blaze, which was been going for roughly 12 hours.

It’s still unclear what caused the fire, but the ‘Sydney Morning Herald‘ is reporting that it is believed that aluminium composite material (ACM) cladding could have contributed to its intensity.

Fire safety engineer Stephen Kip told the paper that fires like this involving combustible exteriors spread quickly:

“All of the fire safety systems in buildings, like sprinklers, are in the inside, not the outside.”

Metropolitan Police Commander Stuart Cundy said that while they could not reveal the number of people believed to be missing, it was expected that the death toll would continue to rise.

In 2016, concerns were raised by a group of residents about the fire safety of the building.

Source: BBC.

Photo: Getty Images / Cal Court.