A burned-out vehicle marks the spot where a gas tanker exploded under a bridge in Boksburg, east of Johannesburg, South Africa, on December 24, 2022. Photo: VCG

Ten people died and around 40 others were injured when a fuel tanker exploded in Boksburg, a South African city east of Johannesburg, emergency services said Saturday.

The tanker, transporting liquefied petroleum gas (LPG), was caught beneath a bridge close to a hospital and houses on Saturday morning.

"We received a call at 7:50 telling us a gas tanker was stuck under a bridge. Firefighters were called to extinguish the flames. Unfortunately, the tanker exploded," said William Ntladi, spokesperson for the emergency services in the region.

One of those injured was the driver who has been taken to hospital, he said. 

He said the death toll had risen to 10 from the nine reported earlier.

Of those injured, around half were in a serious condition while 15 others were seriously hurt but in a stable condition.

Six firefighters also suffered minor injuries, Ntladi said.

Videos on social media showed a huge fireball under the bridge, which the ­tanker appeared to have been too high to go under.

It was carrying 60,000 liters of LPG gas, which is used especially in cooking and gas stoves, and had come from the southeast of the country.

Witness Jean Marie Booysen described a "huge jolt" in the early hours of the morning, shortly after 6:30 am. 

"Today is indeed a very sad day in our little suburb," she said, standing near a forensics team combing the scene.

"I went upstairs to have my cup of tea and I saw immense flames; I thought a house was on fire."

She said she later learned of the deaths of "two children here across the road, 16, the girl, and 25, the boy, who came and did my lawn every weekend for me."