A substation in Randfontein exploded and burst into flames, Eskom confirmed in a tweet early on Saturday morning.
The fire department was attending to the scene, while the cause of the explosion was not known.
In a statement, the utility said several areas in and around Randfontein had been left without power as a result, and technicians would only be able to restore service once it was safe to do so.
@Eskom_SA substation in Randfontein has exploded and is burning. The cause of the fire is unknown. The Fire department is on the scene.
More information to follow pic.twitter.com/HN7IcSFDtp
— Eskom Hld SOC Ltd (@Eskom_SA) April 6, 2019