A British Airways flight was struck by what is believed to have been a drone as the aircraft positioned to land at Heathrow Airport.
Detectives are investigating after an object hit the front of the passenger plane as it approached Heathrow’s Terminal 5 at around 12.50pm.
The pilot was able to land the BA727 flight from Geneva safely, police said.
British Airways said the aircraft was examined by engineers and cleared for its next flight following the incident.
A CAA spokesperson said: "The CAA is aware of a possible incident with a drone at Heathrow today which is subject to investigation by the Metropolitan Police.
"Safety is our first priority. Anyone operating a drone must do so responsibly and observe all relevant rules and regulations. The rules for flying drones are designed to keep all airspace users safe."
"It is totally unacceptable to fly drones close to airports and anyone flouting the rules can face severe penalties including imprisonment."