A plane approaching Heathrow Airport is believed to have hit a drone before it landed safely, the Metropolitan Police has said.
After landing, the pilot reported an object - believed to be a drone - had struck the front of the Airbus A320.
Aviation police based at Heathrow have launched an investigation.
Police said no arrests have been made.
If confirmed, it is believed to be the first incident of its kind in the UK.
A British Airways spokesman said: "Our aircraft landed safely, was fully examined by our engineers and it was cleared to operate its next flight."
The airline will give the police "every assistance with their investigation", the spokesman added.
A Civil Aviation Authority (CAA) spokesman said it was "totally unacceptable" to fly drones close to airports, and anyone flouting the rules can face "severe penalties, including imprisonment".
Steve Landells, from the British Airline Pilots Association (Balpa), said it had been "only a matter of time before we had a drone strike". He called for greater enforcement of existing rules.
Read more: Drone hits British Airways plane approaching Heathrow Airport - BBC News