The buyer of the Gupta's coal assets, Tegeta, appears to have hidden assets for the Gupta family in the past, amaBhungane and Scorpio reported on Thursday.
The Gupta family announced the sale of Tegeta to a Swiss company called Charles King SA, owned by Amin Al Zarooni, on Wednesday.
But amaBhungane and Scorpio reported that Al Zarooni appears to have fronted for the Guptas in the past, when the family wanted to set up a corporate structure for Kamal Gupta, Ajay Gupta's son, in Dubai.
This arrangement was allegedly to hide the Gupta family's ownership of the structure.
Al Zarooni appears as one of the directors of a company established by the Gupta family in Dubai -- an apparent attempt to hide identities of the real owners, the Gupta family, possibly for tax purposes.
Al Zarooni reportedly travelled to South Africa in October 2015, a few months after arrangements were made to establish the fronting vehicle. This was around the time that the Guptas, through Tegeta, were trying to buy Optimum mine from Glencore.
The GuptaLeaks emails reportedly show that Al Zarooni was part of a delegation of officials from the United Arab Emirates, who travelled to South Africa "at the invitation of our business associate, Sahara computers... to explore investment opportunities in the mining sector." Sahara is owned by the Guptas.