An image taken from video shows a Singapore Airlines Boeing 777-300ER sitting on the tarmac at Bangkok's Suvarnabhumi Airport surrounded by emergency vehicles on May 21, 2024, after Flight SQ321 from London to Singapore was diverted after encountering severe turbulence. PONGSAKORNR RODPHAI/REUTERS

Singapore Airlines said Tuesday that one person died and others were injured when a flight from London to Singapore hit severe turbulence. Flight SQ321 from London's Heathrow Airport was diverted to Bangkok and touched down just before 4 p.m. local time Tuesday at Suvarnabhumi Airport, the airline said in a statement posted to its Facebook page.

"We can confirm that there are injuries and one fatality on board the Boeing 777-300ER," the statement said, adding that there were 211 passengers and 18 crew members on the plane. CBS News partner network BBC News later reported that the fatality was a male British passenger aged about 70 who suffered a heart attack during the turbulence, but neither the airline nor Thai officials immediately confirmed those details.

The airline did not say how many were injured, but Thai media outlets said first responders were treating roughly 30 people. Video from Suvarnabhumi Airport showed passengers coming down a ramp onto the tarmac from the plane, which was surrounded by emergency vehicles.

Several people could be seen laying on a tarp under a tent in a triage area crowded by airport and medical staff.

The airline offered "its deepest condolences to the family of the deceased" and said it was providing assistance to all passengers and crew from the flight.

Boeing also offered condolences to the family of the passenger who died in a statement posted on social media. The U.S. aerospace giant said it was in contact with Singapore Airlines and ready to support the carrier as it looked into the incident.

Tracking data from the FlightAware website showed the Singapore Airlines plane dropping suddenly from an altitude of about 37,000 feet to 31,000 feet in the space of only about five minutes. The drop came about 11 hours into the flight from London as the Boeing finished crossing the Andaman Sea and approached the Thai coast.

"Suddenly the aircraft starts tilting up and there was shaking, so I started bracing for what was happening, and very suddenly there was a very dramatic drop, so everyone seated and not wearing seatbelt was launched immediately into the ceiling," passenger Dzafran Azmir told the Reuters news agency. "Some people hit their heads on the baggage cabins overhead and dented it. They hit the places where lights and masks are and broke straight through it."

Another passenger, Andrew Davies, who spoke with BBC News on Tuesday about the harrowing flight, posted a series of messages on social media earlier describing the incident.

"Awful experience," he said. "Lots of people injured — including the air stewards who were stoic and did everything they could."

Davies said there was "very little warning" before the plane plummetted, but that the seatbelt warning light had come on.

"I put on my seatbelt straightaway then the plane just dropped," he said, describing chaos in the cabin as people shouted for a defibrillator and passengers with medical training tried to assist those injured.

"One of the Singapore Airlines crew said it was by far the worst in her 30 years of flying," Davies said in one tweet, adding: "Lesson is — wear a seatbelt at ALL TIMES. Anyone who is injured, was not wearing a seatbelt."

While in-flight turbulence is increasingly common on many routes, deaths and serious injuries are rare. Four people were injured by severe turbulence on a domestic U.S. flight in Florida in July 2023.

Climatologists have warned travelers to brace for more flight delays and cancellations and more frequent and more severe turbulence, especially on routes over the world's fast-warming oceans, as a result of climate change.

CBS News climate producer Tracy Wholf says the impacts of climate change on air travel are far broader than just increasing turbulence, with airports being affected by exacerbated flooding, extreme heat and precipitation hindering take-offs and landings and even a rise in mid-air lightening strikes.


Emergency medics assess and treat people affected by severe turbulence on board Singapore Airlines Flight SQ321, in a triage area at Bangkok's Suvarnabhumi Airport, May 21, 2024, after the flight from London to Singapore was diverted to the Thai airport. PONGSAKORNR RODPHAI/REUTERS