City Power said on Friday technicians were working to restore electricity to suburbs across Gauteng plunged into darkness during heavy rains.

Affected regions include the Johannesburg city centre, as well as areas north and east of the city.

Meanwhile, emergency officials are on high alert in low-lying areas as heavy rains continued on Friday afternoon.

The Tshwane Disaster Management warned there may be flash floods in parts of the capital.

"The areas that are mostly vulnerable to flooding are Centurion, Mabopane, Soshanguve, Ga-Rankuwa and Hammanskraal," said the city's Console Tleane.

Johannesburg emergency services officials are monitoring informal settlements along the Jukskei River and in Kliprivier.

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