REUTERS/Denis Balibouse
HSBC Regional CEO for Global Private Banking in EMEA Alexandre Zeller gestures during the Reuters Global Wealth Management Summit in Geneva October 5, 2011.
According to the BBC, Financial Times, and AP, Swiss prosecutors confirmed it is investigating "HSBC Private Bank (Suisse) SA and persons unknown for suspected aggravated money laundering".
In a statement, Swiss prosecutors said its probe into the troubled bank could be extended to "people suspected of committing or participating in money laundering."
"A search is currently underway in the premises of the bank, led by Attorney General Olivier Jornot and the prosecutor Yves Bertossa," said Geneva's prosecutor.
HSBC is alleged to have repeatedly helped its richest clients hide and dodge taxes in their home countries. The allegations stem from the largest financial data leak of its kind in history.
Around 140 journalists from 45 different countries helped unearth the secret accounts in Switzerland after Herve Falciani, an HSBC whistleblower turned employee, leaked it to French authorities.
Regulators in Belgium, France, Argentina, the US and Switzerland said they would individually consider examining 100,000 of HSBC's clients' accounts in a bid to root about mass tax avoidance.