More banks besides Royal Bank of Scotland (RBS) are expected to be fined for manipulating the London interbank offered rate, Reuters reported Thursday, citing sources familiar with a bilateral investigation.

Regulators in the U.S. and U.K. are expected by midyear to penalize other financial institutions that allegedly conspired to rig the Libor, a benchmark that determines the price at which banks lend to one another, the report said.

JPMorgan Chase (JPM), Citigroup (C) and Deutsche Bank (DB) all are said to be in regulators' crosshairs and among top candidates for settlements, according to the report.

All three companies have acknowledged the probes and said they are cooperating with the inquiries. The companies also face a series of class actions in federal court in Manhattan that accuse them of understating their borrowing costs and misleading investors.

Deutsche Bank suspended five bankers on Wednesday after conducting an internal inquiry into Libor-setting. The bank suspended two employees last year. "Upon discovering that certain employees acted inappropriately, we have suspended or dismissed employees, clawed back unvested compensation and will continue to do so as we complete our investigation," Deutsche Bank spokesman Duncan King said.

A Citigroup spokesman declined to comment. A spokesman for JPMorgan Chase did not respond immediately to a request for comment.

On Wednesday, RBS agreed to pay $612 million in response to investigations by the Commodity Futures Trading Commission, the Justice Department and Great Britain's Financial Services Authority into the company's rate-setting role.

Both UBS and Barclays paid a combined $2 billion last year to settle similar probes.

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