Mitsubishi has suffered a loss of more than $90-million in China after uncovering suspected fraud by one of its copper traders, according to people familiar with the matter.

The loss is the latest in a string of recent cases of alleged wrongdoing to hit a major commodity trading house, highlighting the risk that individual traders who handle billions of dollars in commodities may seek to enrich themselves at the expense of their own companies.

In October, Trafigura Group said it was facing a $1.1-billion hit in Mongolia involving suspected wrongdoing by its own employees. While the scale of Mitsubishi’s loss is considerably smaller, it has nonetheless sent a chill through the huge but conservative Japanese trading house.

Mitsubishi dismissed Gong Huayong, a Shanghai-based copper trader at one of its China units, after finding that he had made unauthorized trades with local companies, including some that were related to him, the people said. The losses amounted to well over 600-million yuan ($82.8 million), they said, declining to be identified as they aren’t authorized to speak publicly.

That matches a loss of 13.8-billion yen ($92.2-million) that Mitsubishi disclosed in its most recent quarterly results, citing a “loss in Chinese trading business,” without further explanation. The hit was primarily the result of Gong’s actions, the people said.

A spokesperson for Mitsubishi confirmed that Gong had been dismissed by the Chinese unit and added a criminal complaint had been filed. The company will cooperate fully with authorities, the spokesperson said, declining to comment further on what it said was now a criminal matter.

Calls and messages to Gong’s mobile phone did not go through, and an email inquiry to his company address was rejected. Several traders in China, who used to have business connections with Gong, said they also could not reach him. These traders asked to be not named due to the sensitivity of the case.

Mitsubishi began investigating Gong’s trades earlier this year, after some customers in its copper business failed to settle trades or defaulted on payments that were due, the people said.

The Japanese company found that Gong, a Chinese national who worked as a trading manager at Mitsubishi Corporation RtM China, had caused Mitsubishi to allow certain local companies to defer payment for copper concentrate and refined copper. In some cases Mitsubishi had not approved the companies as counterparties, and in some cases the companies had personal ties to Gong.

Some of the people said they believed Gong had left China on business even before his actions were fully uncovered by the company, and then did not return. At least one of Mitsubishi’s counterparties, which helped to reveal the alleged fraud after an internal investigation, has reported the matter to the Chinese police. The Shanghai police did not respond to multiple requests for comment.

For Mitsubishi, one of Japan’s major trading companies, known as sogo shosha, the loss is highly embarrassing but manageable. When it reported second-quarter results last month, the company reiterated its full-year profit guidance of 950-billion yen.

Still, it’s far from the first trading scandal to hit the sogo shosha. Most famously, Sumitomo lost more than $2-billion in the 1990s on copper bets made by its star trader Yasuo Hamanaka that the company said were unauthorized. Hamanaka was sentenced to eight years in prison after pleading guilty to forging documents to make unauthorized copper trades on behalf of the company.

Mitsubishi shut its Singapore-based oil unit in 2019 after saying a rogue Chinese trader lost more than $300-million. (The trader said through his lawyer that he was acting on his managers’ orders and that the losses resulted from “premature” settlement of the derivatives positions.)

The latest scandal is likely to make Mitsubishi, already one of the most conservative trading houses, even more cautious, the people said. The company’s Chinese employees in particular are concerned that they may bear the brunt of any fallout.