Video | Brazilian authorities searching for 44 people after Sao Paulo skyscraper burns down, in scenes reminiscent of 9/11

Forty-four people were listed as still missing on Wednesday after a 24-storey building used by squatters in central Sao Paulo was engulfed in fire and collapsed, the Brazilian city’s fire department said.

In the immediate aftermath of the disaster on Tuesday only three were unaccounted for, including one man who was seconds from being successfully rescued by firefighters before the building suddenly crashed down.

“The fire department is continuing to search, currently with 31 vehicles, 78 firefighters,” the department tweeted. “44 missing.”

There was no indication whether the large number of missing were considered likely to have been killed and buried under the rubble, or whether they simply were not there at the time.

The building, a disused former police headquarters, was occupied by 146 homeless families, officials say, blaming lack of even basic fire prevention measures for the accident.

At the moment the building fell, a firefighter atop a neighbouring building had been trying to save someone from the upper floors. TV images showed the person clinging to the building’s side, while apparently also attached to a rope that the firefighter was holding. Then the wall the person was clinging to started to fall away, taking the person with it. The floors of the burning building collapsed like dominoes, while debris flew in all directions, and a giant fireball briefly filled the street.

Authorities later said that the person killed was the one the firefighter had been trying to save, and a body had not yet been found. Firefighters were using dogs to search for that person and any others in the rubble.

The building, a former federal police headquarters, caught fire around 1.30am local time. Firefighters set up a perimeter and worked to evacuate people.