Harmony Gold Mining on Friday reported three fatalities at its Phakisa mine in the Free State.
The company said the employees died in an underground explosion late on Thursday night.
Two other employees were seriously injured and are being treated at the local hospital.
The employees were part of a Mine Rescue Team that was busy investigating a suspected fire in a raise, underground at the time of the accident.
All other employees working underground at the time of the explosion were accounted for and are safe, Harmony said.
The explosion occurred at about 22:30 on Thursday, some 2,013 metres below surface.
“Management together with the representatives of the Department of Mineral Resources worked through the night on the rescue operation. Investigations into the causes of the accident will be conducted once the area has been declared safe,” the company said.
Source: I-Net Bridge