Switzerland has launched a criminal investigation into several bankers that are allegedly involved in the manipulation of the currency markets.
The Swiss prosecutor confirmed in a statement that it is honing in on several traders that are said to have attempted to rig foreign exchange rates as well as colluding with other bankers at different institutions to benefit their financial positions.
However, the agency did not confirm how many people they were looking and at what banks are involved in the probe.
The public prosecutor said the investigation stems from claims of "unfaithful financial management" and "violation of professional secrecy", both of which are punishable with a fine or up to five years or three years in prison, respectively.
On 13 November, the FCA and CFTC fined five banks - Citibank, HSBC, JPM, the Royal Bank of Scotland (RBS) and UBS - a combined total of $3.4bn (£2.1bn, €2.7bn) for their role in the manipulation of the foreign exchange market.
Other authorities have hit a number of these banks with extra penalties.
Citi has confirmed that it will pay around $1bn in fines to three separate authorities after the Office of the US Comptroller of the Currency (OCC) hit the group with another $350m fine.
Meanwhile, the Swiss Financial Market Supervisory Authority (Finma) also concluded enforcement proceedings against UBS and ordered the lender to disgorge a total of $139m.
It has also initiated enforcement proceedings against eleven people involved in the case.
The US Federal Reserve has since confirmed that it is investigating a number of unnamed banks for improper conduct around the currency markets and is working with the Department of Justice and overseas authorities.