The Telegraph is reporting this:
Air passengers are suffering major disruption at airports around the world after computer check-in systems crashed. Travellers have reported problems at London Gatwick, Charles de Gaulle in Paris, Reagan Airport in Washington DC, Changi in Singapore, Johannesburg and Zurich. Passengers are reporting long waits at check-in desks after the outage on Thursday morning. The cause is currently unclear.
11:12am
Update: 'Things back up and running' at Gatwick
Gatwick Airport has just got back in touch.
"Things are back up and running after a momentary IT glitch," a spokesman said.
It is not clear if the issue has been fixed at all airports
11:10am
Gatwick Airport: Check-in software affecting multiple airlines
A Gatwick Airport spokesman said: "This is an airline issue, not an airport issue. This isn't Gatwick software, it's hit a few airlines' check-in systems which are down.
"They are using Altea software and there are several airlines that use the same software for check-in and it's that which is affected.
"They cannot check the passengers in."
The spokesman could not confirm which airlines are affected.