The wheels of justice are now in full swing after former Eskom acting chief executive Matshela Koko, his wife Mosima, and stepdaughter Kokesto Choma were arrested on Thursday.

The trio was arrested by the NPA's Investigating Directorate on charges of corruption over a multibillion-rand contract awarded to Swiss engineering company Asea Brown Boveri (ABB) in 2015.

ABB reportedly subcontracted to a local company, Impulse International, where Choma was a shareholder.

She allegedly received R30 million from the deal.

A portion of that amount allegedly made its way to the pockets of Mosima.

Matshela Koko recently sealed a power purchase agreement with the Zimbabwe Electricity Transmission and Distribution Company.

Matshela was fingered as an instrumental player that opened the doors at Eskom for the controversial Gupta family to capture the ailing power utility during the judicial commission of inquiry into state capture.

In his final report, Zondo recommended that Koko be criminally investigated for the questionable deals at Eskom during his tenure - including the ABB deal and the Guptas' Tegeta deal.

Thabo Owen Mokoena, the owner of Leago Engineering, which was initially awarded an R96 million subcontract by ABB before Impulse International, was also arrested.

NPA spokesperson Sindisiwe Seboka said: "The accused are to be arraigned on charges arising from alleged irregular contracts granted for the building of Kusile Power Stations valued at over R2 billion.

"The accused were in Gauteng and Mpumalanga this morning at the crack of dawn."