The head office of the defunct Swissair Group has been raided by Zurich's judicial authorities.
Mario Corti, former CEO of the bankrupt airline group, confirmed reports that documents had been seized during a day-long search on Tuesday.
The authorities have not revealed the exact nature of the investigation. But Hanspeter Hirt, a Zurich prosecutor, told the "NZZ" newspaper that it was part of a routine probe to determine whether any potential false accounting or "creative bookkeeping" had taken place.
The Swissair Group - which is the parent company of Swissair - collapsed last year, grounding the airline and forcing the group into receivership.
Room full of documents
Hirt said the investigation could take at least three years to carry out because of the number of documents involved.
Investigators removed around three cubic meters of documentation from the company's office in Balsberg near Zurich.
On Thursday, the cabinet indicated that the federal government did not intend to investigate the role of Mario Corti and others involved the Swissair debacle. It added that it would leave the inquiry to the administrator appointed to wind up the defunct group's affairs.
swissinfo with agencies