U.S. officials are investigating at least 10 major banks for possible rigging of precious-metals markets, even though European regulators dropped a similar probe after finding no evidence of wrongdoing, according to people close to the inquiries.

Prosecutors in the Justice Department’s antitrust division are scrutinizing the price-setting process for gold, silver, platinum and palladium in London, while the Commodity Futures Trading Commission has opened a civil investigation, these people said. The agencies have made initial requests for information, including a subpoena from the CFTC to HSBC Holdings PLC related to precious-metals trading, the bank said in its annual report Monday.

HSBC also said the Justice Department sought documents related to the antitrust investigation in November. The two probes "are at an early stage," the bank added, saying it is cooperating with U.S. regulators.

Also under scrutiny are Bank of Nova Scotia , Barclays, Credit Suisse, Deutsche Bank, Goldman Sachs, J.P. Morgan Chase, Société Générale, Standard Bank Group Ltd. and UBS, according to one of the people close to the investigation.

Bank representatives declined to comment or couldn’t be immediately reached. A CFTC spokesman declined to comment, as did a spokeswoman for the Justice Department.

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