WATCH: Koedoespoort Substation goes up in flames, no determination yet how long repairs will take

A transformer inside the substation went up in flames, sending a thick black cloud into the sky and leaving hundreds of residents without power.

City spokesperson Selby Bokaba says the outage affects various areas across regions are 2, 3 and 6.

"The Tshwane Emergency Services was informed about the incident and resources from two fire stations were dispatched to the scene. Firefighters managed to extinguish the fire as soon as technicians switched off the power supply and rendered the area safe for operations.

"The Energy and Electricity Department is currently on site assessing the extent of the damage. Prior to the explosion, our technicians were busy with repair work at the said substation following multiple cable theft two weeks ago."

Bokaba says it is too early to estimate when electricity will be restored, as the testing is still underway.

"Transformer 1C had been soaked and left to idle - meaning that it was not connected to any end-user. Unfortunately, when it exploded, it affected Transformer 1B which feeds some secondary substations in Region 2. 

"The EED team is currently testing the integrity of the overhead lines in order to determine which areas can be switched back on."

Affected suburbs include Waverley, Moregloed, Bergtuin, Koedoespoort industrial, Weavindpark, Lindopark, Eastlynn, Jan Niemand Park, Silverton industrial, Kilnerpark and Queenswood.

Affected secondary substations include Pumulani Primary 132KV Substation, Montana Secondary 11KV Substation, Haartebeesfontein Secondary Substation, Montana, Part of Doornpoort and Breedt Secondary Substation 11KV Substation.

Electricity was restored to some areas through Friday night.

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