Johannesburg — Four men are still in hospital after the accident that killed six people at an Eskom site near Ladysmith, the electricity parastatal said on Friday.
Eskom general manager Gerrie Bronkhorst told reporters in Johannesburg that all four were in an intensive care unit.
"Of those injured, three have been discharged and four are still in the ICU," said Bronkhorst.
The accident happened at Eskom's Ingula pumped storage scheme near Ladysmith on Thursday.
Initial reports from Thursday said only three remained in hospital, but Bronkhorst on Friday said four people were still being treated.
Eskom CEO Brian Dames and chairman Zola Tsotsi expressed condolences to the families of those killed.
"We are determined to make sure that those that died did not die in vain," said Dames.
Tsotsi described the accident as a setback.
"We will leave no stone unturned to uncover what happened."
The men were doing welding and grouting on a platform in one of four tunnels when the platform came loose and rolled down the tunnel.
Eskom said all 3387 workers on site were evacuated and the site would be shut until it was declared safe.