Heathrow Airport investigating 'technical issue' affecting British Airways flights
Heathrow Airport is investigating a technical issue affecting British Airways flights at the West London airport.
Frustrated passengers tweeted about delays to their flights as BA routes faced delays, with some saying they had been unable to check in for hours.
In statement the airport said: "We are working with our airline partner as they investigate and resolve the issue and we are on hand to support any passengers.
"Passengers are advised to check their flight status with British Airways before travelling to the airport, we apologise for any inconvenience cause."
British Airways said it was "working hard" to resolve the issue and apologised to passengers for the inconvenience.
"We will provide further updates as quickly as possible," the airline added.
It has reported the issue is only affecting Terminal 5 and is not part of any global outage.
The problem comes after two major IT glitches that hit the airline's systems earlier this year.
In late February, the airline cancelled all short-haul flights due to a technical problem in an incident that caused delays to stretch into a second day.
The incident was BA’s second outage in 10 days and the latest of several high-profile IT issues to hit the airline.
Last summer, BA settled a legal claim over a major data breach that affected 420,000 customers and staff.
The 2018 breach included the leaking of names, addresses, and card payment details, and led to the Information Commissioner’s Office handing out £20 million fine.
On July 18, 2018, computer problems hit BA operations at Heathrow and the airline cancelled a number of short-haul flights after an incident involving a “supplier IT system”.