UK authorities said the air traffic disruption, which delayed and cancelled multiple flights, was caused by a “technical fault” and not a cyberattack.
Aviation experts said at least 232 flights departing from the UK were grounded. Around 270 arriving flights were also cancelled.
UK Transport Secretary Mark Harper said that getting the flights on their routine schedules would take some days, adding that such instances were very rare.
Dozens of flights were cancelled at Heathrow, Europe’s busiest air hub, which warned of “knock-on impacts.” At least 32 departures from Heathrow were cancelled on Tuesday, and 31 arrivals were axed.
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Gatwick, London’s second-busiest airport, said it planned to operate a normal schedule on Tuesday, but advised passengers to check with airlines before travelling to the airport.
(With AP inputs)