The death toll from a gas tanker that exploded in Johannesburg on Saturday has nearly doubled to fifteen, authorities said, adding that they’d arrested the driver and charged him with culpable homicide.

The blast, which tore the roof off the emergency department at the Tambo Memorial hospital, destroyed two houses, several cars and injured bystanders, occurred when the vehicle caught fire while under a low bridge on Christmas Eve.

“In terms of fatalities … this number has now risen to 15,” including three hospital staff members, Health Minister Joe Phaahla said late on Sunday.

Phaahla suggested that the death toll might later rise because of the nature of the injuries some survivors had sustained in the explosion in the Boksburg suburb of the city.

“We are told that of those who survived, many of them have quite severe burns, so we still have a long way to go,” he said.

Four Zimbabweans, among the dead Thomas Vushendibaba (55), Nathaniel Vushendibaba (19) and Luckson Marufu (40),