13 October 2011 Last updated at 10:57 ET

Rio de Janeiro restaurant blast kills three

The explosion showered Tiradentes Square with debris and disrupted rush-hour traffic

A suspected gas explosion at a restaurant in central Rio de Janeiro has left three people dead and at least 13 injured, Brazilian officials say.

The powerful blast early in the morning caused widespread damage to the restaurant, located in a multi-storey building on Tiradentes Square.

Those killed - who are believed to be staff - were flung out of the building by the force of the blast.

Among the injured, three people are in a serious condition, reports say.

The explosion happened at about 07:30 local time (10:30 GMT), the officials say.

The facade of the building was completely destroyed, and seven floors damaged, Brazilian media reported.

'Smell of gas'

Officials are now checking the building to see if there is a risk of collapse.

Rio de Janeiro Mayor Eduardo Paes said most of the injured were passers-by.

"It was not a greater tragedy because the shops had only just begun to open," he said.

The explosion showered Tiradentes Square with debris and disrupted rush-hour traffic.

The cause of the blast is being investigated, but fire officials say a strong smell of gas was reported just before the incident.

City fire official Ronaldo Alcantara said the restaurant had been closed on Wednesday, which was a holiday, the Associated Press news agency reports.

The official added that gas had probably leaked throughout the day and night, and the restaurant's employees on Thursday morning may have somehow caused a spark that led to the blast.