"How can such a thing happen in a country that claims to be neutral like Switzerland?" co-head of Switzerland's Socialist Party, Cedric Wermuth, asked in an interview with Swiss public broadcaster SRF late Thursday.

He called for a parliamentary inquiry after an SRF investigation broadcast on Wednesday found that a second Swiss encryption firm had been part of a spectacular espionage scheme orchestrated by U.S. and German intelligence services.

A first investigation had revealed back in February an elaborate, decades-long set-up, in which the CIA and its German counterpart creamed off the top-secret communications of governments through their hidden control of a Swiss encryption company called Crypto.