According to reports, Ajay Gupta is behind bars.
City Press reported that Ajay has officially been placed under arrest while his brother, Atul, was in discussions with the Hawks, via his lawyer, to hand himself in.
The newspaper also reported that the number of people arrested, who are allegedly linked to the Vrede Dairy Project, has risen to five.
The Hawks have confirmed that they have made three arrests in their investigation into the controversial Vrede Dairy Farm project in Free State.
Two other suspects are expected to hand themselves in to custody.
City Press reported that a source close to the Guptas' legal team said that Ajay Gupta has been taken in for questioning.
In a statement on Wednesday, the Hawks said their Serious Corruption Crime Unit were conducting ongoing operations at various locations in Gauteng, including at the Gupta family estate in Saxonwold.
Those arrested may appear before the Commercial Crimes Court in Bloemfontein later on Wednesday. City Press also reported that the Hawks are searching for President Jacob Zuma's son, Duduzane.
The Hawks conducted an early-morning raid on the Guptas' mansion in Saxonwold on Wednesday. This follows similar raids at the office of the Free State premier, Ace Magashule, recently.