UPDATE: Switzerland reopens airspace after tech glitch grounds all flights

Swiss air traffic controllers Skyguide announced that flights were gradually resuming from its main international airports Zurich and Geneva from around 8.30am.

"The technical malfunction at Skyguide has been resolved. The airspace closure was lifted at 8.30 am. Swiss airspace is now open again and air traffic over Switzerland and operations at the national airports of Geneva and Zurich are resuming," said Skyguide.

It will likely take a while for flight services to return to normal schedule so passengers should expect disruption throughout the morning. Passengers are advised to check with their airlines if the flights were operating as scheduled.

Zurich airport said flight operations would be at 50-percent capacity until 9:30 am, and 75-percent after that.

"We recommend passengers to pay attention to the flight information of the airline."

Geneva airport said that a number of flights had been cancelled and urged passengers to check with their airlines.

Skyguide said it "regretted the incident" and that it would do everything possible to run flights on time. However it didn't say what the origin of the problem was.

"Skyguide regrets this incident and its consequences for its customers and partners, as well as for the passengers at the two national airports. We are doing everything in our power to handle the flights efficiently and to keep delays to a minimum," read the tweet.

Earlier on Wednesday Geneva airport announced it was forced to close after a computer failure. It was the same news at Zurich where all in bound and outgoing flights were postponed.

At the airports, where the first morning flights were delayed by more than three hours, dozens of travellers crowded around the information screens, with phones plastered to their ears.

The airspace would remain closed "until further notice" read a tweet from airport controller Skyguide.

https://twitter.com/BowlerDerek/status/1536974851847725059

"Technical malfunction at Skyguide – Swiss airspace closed until further notice," the controller said.

"Due to a system failure at Skyguide, no takeoffs or landings are currently possible at Zurich Airport. It is currently not clear how long the interruption will last," read a tweet from Zurich airport.

Skyguide did not give any details about the computer crash, but said it "regrets this incident and its consequences for the clients, partners and passengers of Geneva and Zurich airports and is working flat out to find a solution."

https://twitter.com/zrh_airport/status/1536940130812022785

Swiss international airlines blamed the computer failure on a "technical problem at Skyguide" and said passengers were having to be diverted to airports in neighbouring countries.

"The arriving long-haul flights are currently being diverted to various airports in neighbouring countries, including Milan, Lyon and Vienna. Short-haul flights are currently not taking off," it said.

https://twitter.com/FlySWISS/status/1536950102039961601

The Zurich airport website meanwhile showed that a United Airlsines flight from New York had been rerouted to Frankfurt in western Germany, while a Singapore Airlines flight from the city state had been sent to the southern German city of Munich.

Passengers at airports were obviously hit by delays after the tech failure.

https://twitter.com/HarveyHerridge/status/1536974164711591936