A fire consumed a crowded five-story building in downtown Johannesburg early on Thursday, tearing through an informal settlement of homeless people in what was being described as one of the deadliest blazes in South African history.

Owned by the city, the building once provided emergency housing for women but had become home to a large squatter camp, a sign of the scarcity of affordable housing in South Africa’s most populous city.

These are photographs from the scene.

Residents with some of their belongings bundled up near the scene of the fire.

Firefighters battling to extinguish the blaze. The authorities were working to determine the cause of the fire.

A blanket hanging out of a window that was used to climb out of the building. Residents have described the terror of waking up overnight to the spreading fire.

Women mourning near the building. Some fleeing the fire have said the abandoned site was the only place they could afford to live in the city.

Onlookers watching rescue efforts in the early hours.

The building was one of several places that New York Times journalists visited in May for a report on the chaotic housing situation of South Africa’s most populous city. Neighbors said conditions there were cramped and squalid.

The settlement, pictured here in May, had become a visible symbol of the city’s struggle to address a housing crisis.