London's Heathrow Airport says flight departures have been suspended as a precaution after a reported drone sighting.
The suspension of takeoffs from Britain's busiest airport was announced shortly before 6 p.m. on Tuesday.
Airport officials say they are working closely with police to clarify the situation.
The report follows the pre-Christmas shutdown of London's Gatwick Airport for parts of three consecutive days due to reported drone sightings.
The Gatwick closure led to more than 100,000 people being stranded or delayed, the worst ever drone-related disruption at an international airport.