A fire that erupted at a substation in Eikenhof‚ south of Johannesburg‚ plunging parts of the city into darkness and interrupting the water suppy to several areas could be a deliberate act of sabotage‚ Johannesburg mayor Herman Mashaba said on Tuesday.

"This afternoon‚ it was brought to my attention that City Power officials suspect that the cause of the fire at Eikenhof substation on Monday may have been the result of a deliberate act of sabotage.

"A video has emerged which proves that the fire had originated outside the transformer at the substation. Further to this‚ the transformer appeared to have been maliciously damaged so that it would leak oil onto the fire. These facts are simply not consistent with a fire originating from an electrical fault‚" Mashaba said in a statement.

In the video‚ which appears to have been taken by a City Power employee‚ the employee walks outside and suddenly shouts to his colleagues that there is a fire. He points his camera at the transformer which‚ at the time‚ is spilling oil.

With the camera still in hand‚ he runs back inside the premises to inform his colleagues of the blaze

One of his colleagues is seen running out to tend to the blaze while he follows behind him as plumes of black smoke start to fill the air.

Mashaba said he had since advised City Power to refer the matter to the city’s Group Forensics and Investigation Services (GFIS) and the South African Police Services for further investigation.

"This administration stands for the rule of law and for ensuring that all our infrastructure is effectively utilised for the benefit our residents. We therefore cannot allow criminals to visit wanton acts of crime on City infrastructure‚" he said.

"This substation provides electricity to large surrounding areas of residents and businesses‚ and powers the Rand Water facility in the vicinity. The Rand Water infrastructure‚ powered by this substation‚ pumps water to approximately 40% of Johannesburg‚ as well as parts of the West Rand and Rustenberg. City Power engineers and technicians have worked throughout the night to repair the substation‚" he added.

A new transformer had since been brought in.

Mashaba said it was estimated that power would be restored to residential areas by Tuesday evening.

"At the same time‚ power should return to Rand Water pumps and all affected areas should be fully restored within the next 24 hours‚" he said.

Mashaba vowed to bring the perpetrators to book.

"I will be ensuring that the City‚ working with law enforcement agencies and the NPA‚ bring the perpetrators of this act to justice in the harshest possible manner. When key infrastructure of this nature is vandalised‚ it is a crime against the people of our City‚ our economy and our security‚" he said.