(dailynewyorknews) – Two adjacent buildings collapsed Wednesday evening in the historic center of Rio de Janeiro, injuring at least four people, the mayor Eduardo Paes told reporters.

It was not immediately clear what caused the collapse – a 20-storey building and the stories of other 10 – or the extent of the victims clear.

Paes did not rule out the possibility of a gas leak, but other statements, including the possibility of structural failures in buildings, behind the Municipal Theatre.

Fire officials said at least four people were injured, according to a post on the Twitter account of city government.

“I started to hear a click. I thought they were gunshots. When I looked down I saw the upper floors, “maintenance worker Julio Cesar de Oliveira, told.

A fire broke out after the explosion, told Agencia Brasil. Police and firefighters were to isolate the area and looking for victims, the news agency.

Cars parked on the street near buildings were covered with dust, and there was a strong smell of gas in the region, officials said the fire, according to news agency. The lobby of one of the buildings include a bank and a bakery, Agencia Brasil said.

Witnesses said the band news that shook nearby buildings, as if there had been an earthquake. One witness said many people were inside one of the buildings when it collapsed.

The buildings are in a lively shopping and business district of Rio de Janeiro.

The electrical engineer, said Jorge Draußen Record TV was drinking juice at a nearby restaurant when he saw the little stones that fall from the top of a building.

“I thought it was someone to make a hole for air conditioning,” he said. “From time to time, the building began to fall.”

Source: http://edition.cnn.com/2012/01/25/world/americas/brazil-building-collapse/index.html?hpt=ila_c1