A suspected gas explosion in Johannesburg’s business district in South Africa has killed one person and injured over 40 people.

The blast happened during Johannesburg’s evening rush hour on Wednesday, as many people were gathering on the street to catch a minibus taxi home.

It ripped open roads and flipped more than 20 cars.

Videos shared on social media show a main road split wide open from the force of the explosion, with several vehicles blown onto their side. Huge cracks and holes appeared in the middle of roads, some so big that vehicles slid down into them.

Suspected Gas Explosion Kills One Person in South Africa

The body of the deceased was found during a nighttime search of the blast area, Johannesburg’s Emergency Management Services spokesperson Robert Mulaudzi said on Twitter.

Premier Panyaza Lesufi said 12 people remained in several Johannesburg hospitals for medical treatment. The other 36 people who were hurt had been discharged, he said.

Lesufi said a preliminary inquiry did not establish the cause of the blast.

However, officials suspect an underground gas pipe ruptured, causing the blast.

Meanwhile, specialists have been engaged to determine whether other underground pipes or cables were in the area and if there was a threat of another explosion or gas leak.

“We are still searching for the source,” said Panyaza Lesufi.

Local supplier Egoli Gas said on Thursday that they had found a small leak in one of their pipes, but they believe it is unlikely that it led to the explosion.

The BBC reported that the firm has been asked by authorities to check on their other pipes in the area, as a possible gas leak is still the focus of investigation.