Singapore Airlines has offered compensation to passengers of the ill-fated flight SQ321, which was hit by extreme turbulence that resulted in the death of one passenger and several injuries.

In a statement on its official Facebook page on Tuesday, SIA confirmed it sent out the offers of compensation on Monday to those affected by the flight on May 21.

“For passengers who sustained minor injuries from the incident, we have offered US$10,000 in compensation. For those who sustained more serious injuries from the incident, we have invited them to discuss a compensation offer,” the company said.

Those who sustained serious injuries requiring long-term medical care were offered an advance payment of $25,000 if they requested financial assistance, the airline said adding: “This will be part of the final compensation that these passengers will receive.”

The Singapore-bound flight left London on May 20. About 10 hours after takeoff, the Boeing 777-300ER aircraft experienced extreme turbulence after falling into an air pocket over Thai airspace.

According to investigators, the plane plunged 54 meters (178 feet) in less than five seconds, causing injuries amongst the 211 passengers and 18 crew members on board.

The flight was forced to make an emergency landing in Bangkok where a 73-year-old British national was confirmed dead due to a suspected heart attack. Another 104 passengers were injured, a press officer for Bangkok’s Samitivej Srinakarin Hospital told the Associated Press in May. 

SIA confirmed last week that 20 passengers who were on board the flight were still receiving medical care in hospitals in Bangkok. The airline said it was covering the medical expenses of injured passengers and crew and had arranged for their family members and loved ones to fly to Bangkok when requested.

All passengers on the May 20 flight will receive a full refund, including those who were not injured, the Singapore’s flagship carrier said Tuesday.

In addition to the delay compensation they will receive in accordance with the relevant European Union or United Kingdom regulations, all those on board the flight were also given 1,000 Singapore dollars, or $740, each to meet their immediate expenses when they departed from Bangkok, the airline said.

Following the incident, Singapore Airlines said it had adopted a more cautious seat belt policy and would no longer run hot drink and meal services on flights while the seat belt signs are switched on.

Severe injuries from flight turbulence are considered rare even though turbulence-related accidents are the most common type experienced by commercial airlines, according to the U.S. National Transportation Safety Board.

SIA said in May it has been fully cooperating with an investigation into the incident by the Singapore Transport Safety Investigation Bureau and other relevant authorities.