RIO DE JANEIRO (AP) — A multistory building collapsed in Rio’s centre Wednesday evening, leaving rubble strewn over a wide area but confusion about the number of possible victims and the cause.

Thick layers of debris covered cars and motorcycles. A neighbouring building sustained serious damage, and television showed at least two people on its roof apparently awaiting help from firefighters.

There were differing reports about possible deaths.

A spokeswoman from the city’s Civil Defense department said two people were confirmed dead, but officials from City Hall and the municipal health department later disputed that, saying no deaths had been confirmed by early Thursday. It was not clear how many people were injured.

There was a strong smell of natural gas in the area, but Rio’s mayor said there were doubts that a gas leak caused the accident.

“There apparently was not an explosion. The collapse occurred because of structural damages,” he said. “I don’t think there was a gas leak.” Witnesses had said they heard a loud explosion-like sound just before the building collapsed, and a strong odor of gas hung over the scene.

It was not immediately clear how big the damaged buildings were. The one nearly destroyed was at least five stories high. It sat near Rio’s historic Teatro Municipal and the Fine Arts Museum, both of which appeared undamaged.