20 in ICUs after deadly turbulence on Singapore Airlines flight, Bangkok officials say

HONG KONG and LONDON -- Twenty passengers were being treated Wednesday in the intensive care units at two Bangkok hospitals after a Singapore Airlines flight encountered severe turbulence, hospital officials said.

One person died on Tuesday as Singapore Airlines flight SQ 321 encountered "severe" turbulence, the airline said in a social media post on Tuesday. The Boeing 777-300ER departed London's Heathrow Airport on Monday with 221 passengers and 18 crew members on board, according to the airline.

At least 85 people had been admitted to three hospitals in the Bangkok after the plane was diverted there, Bangkok hospital officials said in a statement released Wednesday. Another 19 were treated at a local clinic, officials said.

The airline had said late Tuesday night that four of the passengers were American. Two of them were injured.

Thirteen patients were still in the intensive care unit at Samitivej Srinakarin Hospital, along with seven at Samitivej Sukhumvit Hospital, officials said.

Thirty-six other passengers were being treated Wednesday at those two hospitals, along with another two at Bangkok Hospital, the statement said. By midday on Wednesday, 27 others had been discharged, the statement said.

Geoff Kitchen, a 73-year-old man from the U.K., died, according to authorities and a music theater group where he worked. Singapore Airlines offered its condolences to Kitchen’s family, saying in a statement on Tuesday, "Our priority is to provide all possible assistance to all passengers and crew on board the aircraft."

The flight, which had been scheduled to arrive at Singapore Changi Airport, instead touched down in Thailand at about 3:45 p.m. local time, the carrier said.

ABC News' Joe Simonetti contributed to this report.