HONOLULU (AP) — A Hawaiian Airlines flight crew's decision to fly over a hazardous storm cell instead of deviating around it was the probable cause for hitting severe turbulence that injured passengers and crewmembers in 2022, the National Transportation Safety Board said in a final report Thursday.

Three passengers and a crew member suffered serious injuries during the flight Dec. 18, 2022, from Phoenix to Honolulu. Twenty people were injured.

According to the report, a crewmember said it reminded him of a “volcanic explosion.” A passenger who had left her seat to go to the lavatory reported that she “flew” face-first into the lavatory ceiling and was “thrown abruptly to the floor.” Cabin damage included missing ceiling panels, a cracked overhead light and a flight attendant handset broken into several pieces, the report said.

In a previous preliminary report, the captain told investigators that flight conditions were smooth with clear skies when a cloud shot up vertically in front of the plane like a plume of smoke and there was no time to change course.

Thursday's report said there were forecasts at the time of unstable atmospheric conditions and isolated thunderstorms. The report determined that the probable cause of the accident was the “flight crew’s decision to fly over an observed storm cell instead of deviating around it” despite meteorological information indicating the possibility of severe turbulence.

“We regularly train our crews on significant weather avoidance, including in-air turbulence,” the airline said in a statement. “Following Flight 35, we conducted a thorough internal review and cooperated with the NTSB to understand the factors that led the aircraft to encounter stronger than anticipated and reported turbulence. We will continue to learn as much as we can from this event.”