U.K. Details Libor Charges Against Ex-Trader

LONDON--British prosecutors said Thursday that former UBS AG (UBS, UBSN.VX) and Citigroup Inc. (C) trader Tom Hayes is accused of conspiring with employees of at least eight other financial institutions in an attempt to manipulate benchmark interest rates.

Mr. Hayes was charged Tuesday with eight counts of conspiracy to defraud, the first person charged in connection with the U.K.'s burgeoning interest-rate-manipulation investigations. He appeared in a London court Thursday for the first time. He didn't enter a plea. His case was transferred to another court, which will hold a preliminary hearing on July 4.

The charges read in court on Thursday indicate that prosecutors' case involves a wide swath of big-name financial institutions. Prosecutors alleged that Mr. Hayes, 33 years old, conspired with employees of Deutsche Bank AG (DB, DBK.XE), HSBC Holdings PLC (HBC, HSBA.LN), J.P. Morgan Chase & Co. (JPM), Royal Bank of Scotland Group PLC (RBS, RBS.LN), Rabobank Group, ICAP PLC, Tullett Prebon PLC (TLPR.LN) and R.P. Martin Holdings Ltd., as well as with former colleagues at UBS and Citigroup.

Representatives of most of those institutions declined to comment or weren't immediately available to comment Thursday. An ICAP spokeswoman said the firm hasn't been charged and has provided information to investigators and continues to cooperate.

Mr. Hayes didn't respond to the charges in court Thursday. He wrote in a January text message to The Wall Street Journal that "this goes much much higher than me."

Write to David Enrich at [e-mail]

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