BBC News - Paul Kirby
Flights in and out of Switzerland were suspended for hours and Swiss airspace closed because of a computer failure at air traffic control service Skyguide.
Geneva and Zurich halted early flights but Geneva airport announced air traffic was gradually resuming.
Skyguide said a technical malfunction in the early hours of Wednesday meant Swiss airspace had had to be closed to traffic for "safety reasons".
Skyguide spokesman Vladi Barrosa told Tagesanzeiger news website that the problem appeared to be a hardware fault and they did not believe their system had been hacked. The company later announced that the "technical malfunction at Skyguide has been resolved" and airspace closure lifted at 08:30 (06:30 GMT).
