The Guardian identifies the flight as BA295 and reports that it was operating on the route from London to Chicago O’Hare Airport.
During the journey, the newspaper continues, the aircraft suddenly and rapidly lost 28,000 feet in altitude while flying over Ireland. The crew then declared an emergency.
During the incident, The Guardian further reports, the oxygen masks were activated and dropped from the cabin ceiling.
The aircraft abandoned the transatlantic flight and returned to the United Kingdom. According to the report, the flight landed safely at London Heathrow Airport.
The Guardian links the incident to a “technical problem” but does not indicate which component or system was involved. The precise nature and cause of the problem therefore remain unspecified in the available information.
Based on the available material, it is not possible to establish whether anyone was injured or what the aircraft’s final technical condition was after landing.