Reuters -- The U.S. Justice Department on Tuesday brought charges against three former traders at JPMorgan Chase & Co, Citigroup Inc and Barclays Plc arising from a global probe into the manipulation of foreign exchange prices at major banks. Richard Usher, formerly of JPMorgan, Rohan Ramchandani, formerly of Citigroup, and Christ Ashton, formerly of Barclays, were charged in an indictment filed in federal court in Manhattan with conspiring to restrain trade. The case came after JPMorgan, Barclays, the Royal Bank of Scotland and a Citigroup unit pleaded guilty in May 2015 to conspiring to manipulate currency prices, agreeing at that time to pay more than $2.5 billion (£2.1 billion) in criminal fines. For more information on U.S. charging three traders in forex rigging probe click on the picture below to learn more.