British Airways passengers around the world are being hit by delays after a glitch took computer systems offline.
A “global system outage” was reported by the carrier.
No figures have been released for the number of passengers hit by the outage, but flights from Heathrow, Gatwick and Belfast have all been delayed.
Heathrow said it was “working closely” with British Airways to address the problems.
Parts of the British Airways website are currently unusable, while the mobile app is also partially offline.
Delays have also been reported in Rome and Malaga airports due to the system failure.