ZURICH -A technical problem with the air traffic control system has halted takeoffs and landings at Swiss airports, the Skyguide agency said.
"The Swiss air navigation service provider Skyguide experienced a technical malfunction in the early hours of this morning, which is why Swiss airspace has been closed to traffic for safety reasons," Skyguide said in a statement.
"This airspace closure is in effect until further notice," it added.
Skyguide said it was working to find a solution and would provide an update when more information was available.
"We now expect flight operations to resume at reduced capacity before midday," Zurich airport said in statement, advising passengers to check information provided by airlines before departing for the airport. It added that check-in was continuing.
Geneva airport tweeted that traffic would not resume before 11 a.m (0900 GMT).