A Swiss prosecutor said on Wednesday it is ordering a search of HSBC Holdings PLC in Geneva and opening an inquiry into allegations of aggravated money-laundering.

"A search is currently underway in the premises of the bank, led by Attorney General Olivier Jornot and the prosecutor Yves Bertossa," Geneva's prosecutor said in a statement.

A spokesman for HSBC in Geneva declined to comment.

Earlier this week, Europe's largest bank apologized to customers and investors on Sunday for past practices at its Swiss private bank after allegations that it helped hundreds of clients to dodge taxes.