A senior official at HSBC has been held in a surprise arrest at JFK International Airport in connection with a case involving currency benchmark rigging, according to reports.

Mark Johnson, the bank's global head of foreign-exchange cash trading, was arrested Tuesday as he prepared to leave the United States, according to multiple reports. He faces charges following a three-year investigation into currency trading practices at multiple global banks.

In addition, Stuart Scott, the former head of the bank's Europe desk, also faces wire fraud conspiracy charges, according to the New York Times, which also reported that Johnson and Scott made a $3 million profit on the trade. The deal in question apparently involved an oil and gas company that wanted to exchange U.S. dollars with British pounds.

HSBC declined comment on the matter. The Justice Department in New York was not immediately available and have not yet released information.

The investigation into currency rigging has been ongoing for three years but has resulted in no individual arrests until this week. Johnson is expected to appear in court Wednesday on a conspiracy to commit wire fraud charge, according to Bloomberg.

Banks have paid billions in fines resulting from investigations, with Citigroup, HSBC, JPMorgan Chase, RBS and UBS forced to pay $3.1 billion in fines from Britain's Financial Conduct Authority and the Commodity Futures Trading Commission in the US. JPMorgan, Citi and Bank of America also had to pay separately $950 million for unsafe practices, while UBS shelled out an additional $138 million to the Swiss Financial Market Supervisory Authority for improper business conduct.