American prosecutors are preparing cases against at least one unnamed U.S. bank and some people for rigging global exchange rates, reports Bloomberg.

Charges against the American bank are expected in 2014, with individual charges coming next year.

Read: U.K. bank executive pleads guilty to LIBOR

Other banks may be charged as well. Regulators in the UK have already brought allegations against banks there, and are in the process of reaching settlements, reports Bloomberg.

The case stems from allegations that traders in London tampered with the benchmark rate at which banks will lend currency to each other. That rate determines margins for transactions worldwide.

Read more here.

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