Updated

A Belgian investigating judge has charged a Swiss private banking branch of HSBC with massive organized fiscal fraud, money laundering and forming a criminal organization to the benefit of over 1,000 wealthy clients that cost the Belgian authorities "hundreds of millions of euros."

The prosecutor's office said in a statement Monday that the accusations against HSBC Private Bank NV/SA are based on its involvement over the years with "wealthy clients, specifically from the Antwerp diamond industry."

Beyond the cost to Belgian taxpayers, the prosecutor's statement said that "much higher sums can be added" from possible money laundering operations that the justice ministry is dealing with.

In August, HSBC Holdings PLC said it knew inquiries were ongoing and "that the fines and/or penalties imposed could be significant."