A burning smell which forced a jet to make an emergency landing at Cardiff International Airport has been traced to an air conditioning fault.
The jet is undergoing safety checks at the airport
The pilot of the Boeing 777 requested permission to land at Cardiff on Friday afternoon after the smell was noticed.
The British Airways flight from Heathrow to Toronto had 274 passengers and 16 crew on board.
Vehicles from the emergency services were summoned to the runway, but were dismissed when it was realised there was no danger.
The plane turned back just over the Irish Sea after requesting a diversion to Cardiff, according to a National Air Traffic Services spokesman.
landed in Cardiff just before 1730 GMT.
A spokeswoman said the plane stopped safely outside the BA maintenance depot after landing.
Engineers were called to examine the aircraft, and the passengers were taken to a hotel and made comfortable.
The passengers and crew later flew back to Heathrow. They will continue their journey to Toronto on Saturday.