The passenger, named as Geoff Kitchen, suffered a suspected heart attack on the flight.
A spokesman for Bangkok’s Suvarnabhumi Airport, where the flight was diverted to, said the 73-year-old suffered a suspected heart attack.
Some international passengers have to apply for an Electronic Travel Authorisation (ETA) when changing planes at Heathrow
The Singapore Airline flight, operated by a Boeing 777-300ER jet, was diverted to Bangkok.
The Singapore Airlines Boeing 777-300ER jet was diverted to Bangkok.
Flight SQ321 made an emergency landing in Thailand after being forced to re-route around 90 minutes from intended destination
‘This requirement will place the UK at an immediate competitive disadvantage’ – Lord Foster of Bath
Airport lounges can be a good way to relax before your flight but they often come with a hefty price. Are airport lounges worth it?
More than 500 Border Force employees are expected to take part in the strikes, which will run from May 31 to June 2 - one of the busiest weekends of the year.
More than 500 union members will walk off the job on May 31 and June 1 and 2
British Airways has grounded 18 flights, while Aer Lingus, Air France and Lufthansa have also cancelled departures
More strikes have been announced by Border Force staff at Heathrow Airport at the back end of half term.