JP Morgan Chase, the largest Bank in the US, has revealed it is under investigation over currency trading. The firm said the US Department of Justice had launched a criminal investigation, other regulators are running civil investigations. It added that possible losses from all its the legal proceedings could total 5.9 billion dollar. A number of other banks, including HSBC, RBS and Barclays, have recently set aside sums to cover similar probes. Other banks, such as Citigroup and UBS, are also being investigated over the alleged rigging of foreign-exchange rates.