South Africa’s wealthy Gupta family, accused in a government corruption probe of allegedly holding undue influence over President Jacob Zuma, said on Tuesday it had asked a court to force a financial regulator to give the family details concerning the closure of its business accounts.

The country’s four major banks, Barclay’s , Standard Bank , FNB and Nedbank early in 2016 terminated the accounts of several companies, spanning mining to media operations, controlled by the family under the Johannesburg exchange listed Oakbay Resources.

The banks refused to make public their reasons for closing the accounts. Analysts have said the banks were likely prompted by concerns about reputational risk.

The Guptas have denied accusations that they have used their friendship with Zuma to advance their interests as well accusations of money laundering and fraud.

In the affidavit the family requested the High Court to force the Financial Intelligence Centre (FIC) to provide details of transactions totalling 6.8 billion rand ($493 million) flagged as suspicious by the regulator in a report to Finance Minister Pravin Gordhan.

An anti-graft probe published this month by the Public Protector focused on claims that the brothers, Ajay, Atul and Rajesh Gupta influenced the appointment of ministers.

It also called for an investigation into whether Zuma, some of his cabinet members and some state companies had acted improperly, triggering renewed calls for the president’s resignation.

President Zuma, who on Monday was facing a motion to remove him by members of his party, the ANC, has said that the Guptas are his friends but denied doing anything improper.

($1 = 13.7952 rand)