A truck carrying liquified petroleum gas exploded in the South African town of Boksburg, east of Johannesburg, on Saturday killing at least nine people and injuring 50 others, officials said.

The top of the truck scraped a low-lying bridge, sparking flames that caused the explosion, according to emergency services officials.

Gauteng province Premier Panyaza Lesufi announced the latest death toll at a news conference but said the figures could be updated.

“This is a sad day. It’s sad day for our province, a sad day for our country. And we want to extend once more our sincerest condolences to the affected families,” said Lesufi.

The tanker was reportedly delivering gas to the nearby O.R. Tambo Memorial Hospital, where some of the injured were treated.

Lesufi said part of the hospital had been badly damaged and had been closed, while checks were ongoing to see whether the entire facility should continue operating.

Tania Campbell, the mayor of Ekurhuleni municipality, was seen touring the explosion site along with other officials.