Two more miners have been killed at Harmony Gold mines, days after an underground blaze that resulted in the death of at least eight workers, the company said on Friday.
The workers were killed in separate incidents at Harmony's Kusasalethu and Joel mines on Thursday and operations at all of Harmony's mines have been suspended, it said.
One man died when an underground support structure collapsed and another one was involved in an explosives accident.
"The accident at Kusasalethu occurred when a backfill paddock and bag failed, which resulted in an employee being inundated by backfill material. At Joel mine, an employee died in a blasting accident," said a statement.
On Tuesday, 17 workers were trapped underground at Harmony's Doornkop operation after an earth tremor that triggered a fire.
Eight of the miners were rescued and another eight were found dead the following day.
A search for the last remaining worker is ongoing.
"The past two days have been tragic for Harmony, having lost our colleagues at three of our operations in three separate events," said Harmony chief executive Graham Briggs.
"This is unacceptable," he added.
The mining ministry has promised to launch a probe into the Doornkop incident.
Accidents are commonplace in South Africa's mines, which are the deepest in the world.
In July 2009, nine workers were killed in a rock fall in a platinum mine.
The same year, at least 82 people digging illegally in an disused gold mine shaft died when a fire broke out underground.