Two current and one former JPMorgan Chase & Co executives were charged over allegedly participating in market manipulation in the trade of precious metals including gold, silver, platinum and palladium between 2008 and 2016, the Department of Justice said in a statement.

The three men – global precious metals desk head Michael Nowak, precious metals trader Gregg Smith, and former trader Christopher Jordan, who left JPMorgan in 2009 – were charged with a racketeering conspiracy and other federal crimes.

“The defendants and others allegedly engaged in a massive, multiyear scheme to manipulate the market for precious metals futures contracts and defraud market participants,” said Assistant Attorney General Brian A. Benczkowski. “These charges should leave no doubt that the Department is committed to prosecuting those who undermine the investing public’s trust in the integrity of our commodities markets.”

“Smith, Nowak, Jordan, and their co-conspirators allegedly engaged in a complex scheme to trade precious metals in a way that negatively affected the natural balance of supply-and-demand,” said FBI Assistant Director in Charge William F. Sweeney Jr. of the FBI’s New York Field Office. “Not only did their alleged behavior affect the markets for precious metals, but also correlated markets and the clients of the bank they represented."

The trio allegedly engaged in “spoofing” on a massive scale – placing bids to buy or offers to sell contracts with the intent to cancel them before execution – dating back over 10 years, openly discussing their illegal behavior in chat logs obtained by the prosecution and included in the indictment.

The DOJ claimed the bankers made millions of dollars by defrauding other market participants, including some of their own clients, in thousands of illegal trade sequences.

Reuters reported on Sept. 12 that Nowak and Smith had been placed on leave from JPMorgan in connection with the ongoing investigation.

A spokesman for JPMorgan declined to comment. The bank said in an August regulatory filing it was “responding to and cooperating with” investigations by various authorities, including the Department of Justice, relating to trading practices in the metals markets.

The charges were the latest turn in a years-long investigation that has previously yielded guilty pleas to illegal spoofing activity from traders at several banks, including two from JPMorgan.

There has been a surge in spoofing-related prosecutions in recent years. Bank of America Corp’s Merrill Lynch commodities unit, for example, paid $25 million in July to resolve actions by the U.S. Commodities Futures Trading Commission and Department of Justice for precious metals spoofing trades between 2008 and 2014.