Incoming flights were grounded at Gatwick airport for almost an hour on Sunday after reports of a drone near the airfield.
Gatwick said 12 incoming flights had to be diverted to other airports due to the alert.
The airport previously canceled or diverted some 1,000 flights over a three-day period in December 2018 as a result of drone reports. No culprit was found and there was criticism over the length of time it took to reopen the runway at West Sussex airport.
A Gatwick spokesperson could not say whether a drone had been discovered after the last reported sighting.
They said: “Passenger safety is the airport’s top priority and, following established procedures, operations at London Gatwick were temporarily suspended at 1:44 p.m. while investigations were carried out into a suspicious drone sighting near the airfield.
“These investigations have now been completed and the airfield reopened at 14:35. Twelve incoming planes were diverted to other airports during the investigation. However, we expect many of them to return to London Gatwick today.”
British Airways said one of its flights was affected. The aircraft landed at Stansted before refueling and returning to Gatwick.