Thai authorities have confirmed that a British man, 73, died on a Singapore Airlines flight on Tuesday after severe turbulence left 30 people injured. 

At a press conference, officials said the man is believed to have suffered a heart attack. Seven people are in a critical condition. 

It comes after a Singapore Airlines flight from London hit severe turbulence and was forced to divert to Bangkok, the airline said.

The Boeing 777-300ER, operating as SQ321 from London to Singapore, landed at Suvarnabhumi Airport in the Thai capital during the afternoon local time.

The plane was carrying 211 passengers and 18 crew members and emergency services rushed to the scene. 

Meanwhile, Boeing, the US manufacturer of the aircraft involved, said it was in contact with Singapore Airlines and offered its support.

"We extend our deepest sympathies to the family who lost a loved one, and our thoughts are with the passengers and crew," Boeing said in a statement following the incident involving the 16-year-old plane. 

Singapore Airlines, which had already expressed its regret over the incident, also issued a further statement giving more details about the flight, which it said encountered "severe unexpected turbulence" over the Irrawaddy Basin, Myanmar at 37,000 feet (11,300m), about 10 hours after take-off.

"As of 1950hrs Singapore time on 21 May 2024, 18 passengers have been conveyed to hospitals. Another 12 are being attended to at the clinics. The remaining passengers and crew are being assessed and provided with medical assistance as needed, at Suvarnabhumi International Airport, Bangkok," it said.

"The passenger nationalities are as follows: Australia 56, Canada 2, Germany 1, India 3, Indonesia 2, Iceland 1, Ireland 4, Israel 1, Malaysia 16, Myanmar 2, New Zealand 23, Philippines 5, Singapore 41, South Korea 1, Spain 2, United Kingdom 47, United States of America 4," it said.

Singapore Airlines "extends our deepest condolences to the family of the deceased customer. We are sorry for the distress that our passengers and crew have experienced on this flight. We are providing all necessary assistance during this difficult time," it added. 

The airline said it was working with the Thai authorities and sending a team to Bangkok to assist.

Speaking to Reuters, a 28-year-old man who was on board the plane described a "dramatic drop" which sent passengers flying. 

Photos from inside the cabin show large gashes in the overhead panels, oxygen masks and panels hanging from the ceiling and scattered hand luggage.

You can also watch a video in the gallery above.

See also: "Dramatic drop". Young man recalls deadly Singapore Airlines flight (Portuguese version)