Two former Eskom senior managers, two business directors and seven companies are expected to appear in the Johannesburg Regional Court on Thursday on charges of fraud, corruption and money laundering.

The suspects can only be named once they have appeared in court.

According to the Directorate for Priority Crime Investigation (Hawks) and National Prosecuting Authority (NPA) the suspects were arrested early on Thursday in Mpumalanga, Limpopo and Gauteng by the Hawks’ serious commercial crime investigation team and the NPA's investigative directorate.

"Investigations began when suspicions were raised into the construction of two large projects at Medupi and Kusile power stations.  This revealed that there was apparent gross manipulation of contractual agreements between contractors, Eskom employees and third parties at Kusile power station," said Hawks spokesperson brigadier Hangwani Mulaudzi via a statement.

"Investigations began when suspicions were raised into the construction of two large projects at Medupi and Kusile power stations.  This revealed that there was apparent gross manipulation of contractual agreements between contractors, Eskom employees and third parties at Kusile power station," said Hawks spokesperson brigadier Hangwani Mulaudzi via a statement.

Mulaudzi said that in June 2015, the Kusile project management team submitted a request to Eskom's procurement committee for a mandate to negotiate and conclude a contract with one of the companies.

The contract was approved in 2015 for R745 million to build two air cooled condenser (ACC) units at Kusile. It is alleged that from February 2015 to July 2017, the appointed companies, other related entities and individuals "shared approximately R30 million amongst themselves".