AT LEAST 31 people are believed to have died in a gas explosion in a disused mine shaft in South Africa in May that is only now coming to light, authorities said today.

Most of the bodies of the suspected illegal miners, believed to have been killed on May 18, remain underground, the Department of Mineral Resources and Energy said.

Authorities are considering their options after being prevented from sending a search team to retrieve bodies from the mine in Welkom, in Free State province, because there were still dangerously high levels of methane gas in the shaft, the government department said in a statement.

Illegal prospecting is rife in South Africa’s old gold-mining areas, where miners go into closed and often dangerous mine shafts to dig for deposits.

The department said it had received information that three bodies had been recovered, having been brought to the surface by other illegal miners.

Another 16 suspected illegal miners who were in the shaft have handed themselves over to authorities, which said they believe the miners to be from neighbouring Lesotho.

The mine, previously owned by Harmony, South Africa’s largest gold-mining company, was last operational in the 1990s, the department said.