A United flight bound for Newark Liberty International Airport was diverted to London on Sunday after multiple passengers said they felt lightheaded and nauseous, the airline has said.
The flight, United Airlines Flight 31, left Munich, Germany around 9am and landed at Heathrow Airport around 1pm.
The crew onboard the Boeing 767-300 decided to divert the plane when it was about 180 nautical miles from London, the reports.
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United Airlines Flight 31 was diverted to London's Heathrow Airport on Sunday. It left Munich, Germany bound for Newark Liberty International Airport
Passengers reported feeling lightheaded and nauseous on the Boeing 767-300 (pictured in a stock photo)
British medical professionals boarded the aircraft and tended to the passengers, video and photos from social media show.
Passenger Pete Teoh tweeted: 'Flight @united #UA31 MUC-EWR diverted to LHR due to several passengers feeling lightheaded. I felt fine. On the ground now awaiting further instruction'.
The Aviation Herald reports that one passenger was taken *** the plane.
All passengers later disembarked and were rebooked on different flights.
It is not yet clear what caused the illnesses.
United says it offered hotel rooms and meals to the affected passengers.
Newark's airport is one of the three principal airports for the New York City metropolitan area.