Swiss intelligence officers are being criticised for ignoring warnings from their US and UK counterparts about the owners of a hotel near the military airbase in Meiringen in canton Bern.
Last summer the hotel was raided and the Chinese owners arrested. They were suspected of spying on the airbase which is due to receive new F-35 fighter jets.
The planes have been a target of Chinese espionage attempts all over the world.
But a report in the Wall Street Journal says the Swiss had been warned about the owners by the CIA and MI6. But those warnings were ignored for a long time.
The newspaper also reports the hotel, which is now up for sale, will be bought by the Defence Department – but that’s not being confirmed.