Swiss authorities have searched HSBC’s Geneva offices as part of a probe into allegations of aggravated money laundering.
Geneva’s prosecutor in a statement said, "A search is currently under way in the premises of the bank, led by Attorney General Olivier Jornot and the prosecutor Yves Bertossa."
The inquiry could later be extended to people suspected of committing or participating in money laundering, the statement added.
The raid follows revelations made by several leading publication which showed how HSBC’s Swiss arm allowed clients to withdraw "bricks" of cash and helped clients conceal their accounts from domestic tax authorities.
The disclosures have initiated a political row in Britain doubting if tax authorities had done enough to pursue possible wrongdoers.
The bank has admitted of falling short of requirements needed to address compliance and controls at its Swiss private bank in the period up to 2007.
HSBC’s Swiss bank CEO Franco Morra said: "New senior management have comprehensively overhauled the business, including closing the accounts of clients who didn’t meet our high standards and ensuring we have strong compliance controls in place."