City Press has learnt that former Sars commissioner Oupa Magashula has also been summoned by the Hawks to make a warning statement along with former acting Sars commissioner Ivan Pillay and former High Risk Investigation Unit head Johann van Loggerenberg.
Highly placed officials within the SA Police Service told City Press that Magashula was expected to make his statement at the Hawks' headquarters in Silverton today.
Magashula resigned from the revenue service in 2013 after an inquiry found he had offered a young woman a job at Sars without following procedure.
This week, the rand and markets plunged after it was revealed that the Hawks summoned Finance Minister Pravin Gordhan, as well as Pillay and Van Loggerenberg to make warning statements at the Hawk's Pretoria headquarters.
Gordhan refused, saying his lawyers had advised him that there was no need for him to do so.
In a statement issued yesterday, Gordhan said: "I am advised that I am under no legal obligation to present myself to the Hawks as directed in their letter."
His statement ended: "I have a job to do in a difficult economic environment and serve South Africa as best I can. Let me do my job."
City Press has also learnt that the docket containing the case against Pillay, Van Loggerenberg, Magashula and Gordhan, compiled by Brigadier Nyameka Xaba, the head of the Hawks's crimes against the state unit, has been handed over to national director of public prosecutions Shaun Abrahams, who is handling the matter personally.
However, Magashula is not the only official besides Gordhan, Pillay, and Van Loggerenberg who has been summoned by the Hawks to make a warning statement, which is a precursor to the launch of criminal proceedings against a suspect.
City Press understands that Oscar Pistorius' prosecutor Gerrie Nel was also expected to make a statement today about the purchase of surveillance equipment allegedly used to bug the National Prosecuting Authority headquarters in Silverton, Pretoria, in an operation that became known as Project Sunday Evenings.
The project was initially designed to prevent the theft of documents from the offices.
An investigation into the NPA's C-fund, which was used to pay for the equipment, is now underway and Nel is also being investigated for his role in the matter and alleged contraventions of the Public Finance Management Act.
City Press has also learnt from senior police sources that some of the protagonists involved in Project Sunday Evenings will be given the chance to turn state witnesses and testify against their former colleagues in exchange for immunity.
Hawks head Mthandazo Ntlemeza and Hawks spokesperson Hangwani Mulaudzi were unavailable for comment.
In February, City Press reported that Ntlemeza was given the green light to pursue the investigation "at the highest level".