Heathrow and Gatwick LIVE: Flights delayed and cancelled after air traffic control outage

Passengers at London Heathrow and London Gatwick have been hit by flight delays and cancellations following Wednesday's radar issues affecting major airports across the UK.

A "radar-related issue" caused the air traffic control (ATC) failure that grounded flights across the UK yesterday, officials have said. National Air Traffic Services (Nats) chief executive Martin Rolfe was summoned to meet Transport Secretary Heidi Alexander on Thursday morning, a day after thousands of passengers were disrupted by the technical problem which forced the cancellation of more than 150 flights.

Airlines are demanding an explanation for what happened. A spokesperson for Nats said: "This was a radar-related issue which was resolved by quickly switching to the back-up system during which time we reduced traffic to ensure safety.

"There is no evidence that this was cyber related."

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