A 73-year-old British man died and several others were injured, after severe turbulence on a London to Singapore flight.

Eyewitnesses say the aircraft “suddenly dropped”, causing those not wearing a seatbelt to be “launched into the ceiling”.

According to BBC News, the elderly man is believed to have possibly died of a heart attack.

Meanwhile in a statement, Singapore Airlines said 18 individuals have been hospitalised, while another 12 were being treated in hospitals.

It adds that the the remaining passengers and crew were being examined and given treatment, where necessary.

The flight was carrying 211 passengers and 18 crew, and was forced to divert to Bangkok for an emergency landing.

Singapore Airlines said, “We are working with our colleagues and the local authorities in Thailand to provide the necessary assistance. A Singapore Airlines team is on its way to Bangkok to provide any additional assistance needed.”