Highrise in Brazil's largest city catches fire and collapses, killing at least 1

An abandoned highrise building occupied by squatters in downtown Sao Paulo has collapsed after catching fire, sending chunks of fiery debris crashing into neighbouring buildings and surrounding streets.

Officials are unsure if all the occupants of the building have been accounted for

A firefighter walks past the site of a building that collapsed in downtown Sao Paulo on Tuesday. (Leonardo Benassatto/Reuters)

An abandoned highrise building occupied by squatters in downtown Sao Paulo collapsed on Tuesday after catching fire, sending chunks of fiery debris crashing into neighbouring buildings and surrounding streets.

Firefighters said at least one person had been killed and there could be more.

The building, a former headquarters of the federal police, caught fire around 1:30 a.m. local time. Firefighters set up a perimeter and worked to evacuate people.

A few hours later, as flames engulfed the building of at least 20 stories, it collapsed. Globo TV, which was covering the fire, captured the destruction. Images showed the floors falling on themselves like dominoes and debris flying in all directions.

Reports say abandoned tower may have housed around 150 squatters 1:10

By late Tuesday morning, several families who had fled the building were camping out in front of a nearby church, where neighbours and local businesses were dropping off supplies: bags of bread, milk, bottles of water and even some bags of used clothing or shoes.

​Lohany Michely, 37, said she was asleep with her boyfriend and dog in their apartment on the third floor of the building when she began hearing people yell about a fire. Seeing smoke, the couple left with their dog, then watched the building collapse about 45 minutes later.

"Entire families lost everything," she said. "People think that people who live in an occupation are animals. We are not animals. We are human beings."

Firefighters work in the the rubble on Tuesday, hours after the building collapsed. (Andre Penner/Associated Press)

Romulo de Souza, 49, said he was part of a squatter occupation in the neighbouring building. He said that when the fire began on the fourth floor of the former police headquarters, families began evacuating.

"Happily the majority got out," he said.

De Souza said that residents believed the fire could have been started by a gas leak.

Lt. Andre Elias of the fire department told Globo TV that at least one person died. Authorities were working to locate several others who were missing.

Squatters occupy dozens of buildings

Clearing debris and accounting for people who had been in the building could likely take days. Four hours after the collapse, smouldering debris continued to emit smoke.

The fire and collapse are sure to put a spotlight on occupations in Sao Paulo, South America's largest city. Several dozen buildings have been occupied in downtown by highly organized fair-housing groups that take over and then fight for ownership. Many such dwellings are run like regular apartment buildings, with doormen and residents paying monthly fees and utility bills. Others are less established and more precarious.

A police officer comforts a woman near the site of the building collapse. (Leonardo Benassatto/Reuters)

In a June 2017 story on the occupations, The Associated Press reported that around 350 families were living in the former police headquarters. Local media on Tuesday reported that only around 50 were currently living there, while Reuters said the building housed around 150 people.

Former Sao Paulo mayor Joao Doria, who recently stepped down to run for governor, cracked down on squatter communities as a plan to revitalize the downtown.

Doria argued the downtown should showcase Sao Paulo, the engine of Brazil's economy and one of the hemisphere's most important financial centres. Fair-housing activists, on the other hand, argue that the area could offer affordable housing to tens of thousands of people.

Smoke rises as firefighters work in the rubble. (Andre Penner/Associated Press)

Sao Paulo state Gov. Marcio Franca said about 150 buildings in the region were occupied by organized groups of squatters, who have pressured the government for years to provide housing for the homeless.

The governor said it was legally difficult to force people to evacuate the old and decaying buildings.

During a brief visit to the area Tuesday, President Michel Temer told reporters that the government would help those affected by the fire.

"We will provide assistance to the victims of this disaster," said Temer, who has been charged with corruption and has approval ratings in the single digits. He did not provide details and was whisked away by security as several people shouted obscenities at him.

With files from Reuters