A Swiss court ordered an unnamed whistleblower not to discuss allegations of accounting fraud at zinc producer Nyrstar NV, an affiliate of Trafigura Group Pte. Ltd., with any third parties, according to a Bloomberg News report.

The gag order comes after regulatory authorities in Belgium initiated an investigation of Nyrstar in August based on the allegations.

Nyrstar has denied the allegations, according to Bloomberg.

Trafigura, a commodities trading company, acquired control of Nyrstar earlier this year amid a restructuring that angered some Nyrstar shareholders.

A group of investors alleged in a lawsuit that Trafigura pushed Nyrstar to accept unfavorable contracts, which contributed to the company's financial instability. Nyrstar has said the claims are "entirely incorrect."