Geneva's public prosecutor searched HSBC's lakeside Swiss office on Wednesday after opening a criminal inquiry into allegations of aggravated money laundering, the second probe to hit the bank this week.

Europe's largest lender is in regulators' sights after details about how its Swiss private bank allegedly helped wealthy clients dodge taxes were leaked to the media and published last week.

In an unusual move, the Geneva prosecutor's office notified the media of the raid as it was going on. It searched two HSBC offices and said its investigation could target individuals, who would be liable to a fine and up to five years in prison if found guilty of serious money laundering offences.