Flights have now resumed at Gatwick Airport in London.
They were suspended for a time this evening - because of a "suspected drone sighting".
Authorities at the airport say they're reassured by anti-drone measures put in place after yesterday's all-day disruption.
Flights have now resumed. Airfield movements were suspended while we investigated this as safety remains our main priority. The military measures we have in place at the airport have provided us with reassurance necessary to re-open our airfield.
— Gatwick Airport LGW (@Gatwick_Airport) December 21, 2018
Drones caused Gatwick to close for more than thirty hours until early this morning.
Flights resumed today with some disruption.
Yesterday, cancelled flights stranded tens of thousands of passengers days before Christmas.
Police and airport authorities believe they were being flown in deliberate act to disrupt the airport.
Grounded aircraft next to a terminal at Gatwick Airport in London | Image: Pete Summers/PA Wire/PA Images
Gatwick's chief operating officer Chris Woodroffe says it was a "terrible situation" for the 120,000 people who have had their travel plans disrupted.
"The issue from my perspective is that this is a criminal act, purposefully undertaken in order to cause this disruption, and I very much hope we bring the perpetrator to justice."
Aer Lingus earlier said they intended to operate all Gatwick flights today.
We intend to operate all flights to/from Gatwick today, subject to airspace remaining open. However, there are delays on all Gatwick flights so please check flight status before travelling. We're working hard to ensure everyone gets to their planned destination for Christmas ðŸŽ„
— Aer Lingus (@AerLingus) December 21, 2018
While Ryanair said its flights scheduled to operate to and from London Gatwick on Friday will instead operate to and from London Stansted.
Travel update: Ryanair flights scheduled to operate to/from London Gatwick tomorrow (21 Dec) will instead operate to/from London Stansted. All affected customers have been notified by our Customer Care team https://t.co/96cDH8V0oJ
— Ryanair (@Ryanair) December 20, 2018