JOHANNESBURG — At least 73 people have died and dozens more were injured after a fire tore through a five-story building in central Johannesburg which housed “hundreds” of informal settlements.

Authorities said they have moved through the building floor by floor, searching for survivors and pulling out charred bodies and laying them on the streets. Children are believed to have been killed, according to local media.

The fire has now been extinguished, rescue officials said.

In addition to the dead, more than 50 other people were injured, according to Robert Mulaudzi, a spokesperson for the city’s emergency services.

Videos taken moments after the fire broke out show huge orange flames engulfing the lower floor of a building and scores of people standing outside.

Photos from Thursday morning showed onlookers crowding around burnt-out and cordoned-off areas, broken glass windows, and clothes strewn around the building.

The cause of the blaze remains unclear but authorities at the scene gave no indication it was deliberate. The fire broke out around 1:30 a.m. local time, when many people inside the building were asleep.

It took place in a “hijacked” building in central Johannesburg, Mulaudzi said, referring to what he said were “hundreds” of settlements inside.

“Hijacked” buildings, seen in many parts of downtown Johannesburg, refer to buildings abandoned by landlords and taken over by gangs or other groups and leased out mostly to migrants and South Africans who don’t have the means to afford other forms of housing.

This form of housing often fails to meet basic safety regulations. Local authorities on the scene described the building as like an informal settlement, saying the apartments in the building, intended only to house two or three people, were partitioned into sleeping areas to accommodate multiple people.

“Hijacked buildings” have been condemned in South Africa and attempts have been made to bring in regulations. Authorities have been criticized by some South Africans for failing to tackle the problem.

South Africa has seen other devastating fires in informal settlements across the country in recent months. — CNN