On Sunday morning, Hawaiian Airlines flight 35 from Phoenix to Honolulu was rocked by turbulence that sent unbuckled passengers’ heads crashing into the plane’s ceiling.

Per a Fox News report, 36 injured passengers were treated by Honolulu Emergency Medical Services, with 11 taken to emergency rooms in serious condition.

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Hawaiian Airlines released a statement confirming the incident: “HA35 from PHX to HNL encountered severe turbulence & landed safely in HNL at 10:50 a.m. today. Medical care was provided to several guests & crewmembers at the airport for minor injuries while some were swiftly transported to local hospitals for further care.”

The turbulence is believed to have been caused by a strong low-pressure storm over the Hawaiian Islands on Sunday.

Videos of the incident have begun popping up on social media.

OMG PLEASE PRAY FOR MY ISLAND Y’ALL ????

NOT ONLY WAS THERE A TORNADO ON MOLOKAI BUT THA TURBULENCE ON A @HawaiianAir FLIGHT FROM PHX TO HNL WAS SO BAD IT SENT HELLA PASSENGERS TO THA HOSPITAL STRAIGHT OFF THA TARMAC.. I’M PRAYING FOR EVERYONE SUSTAINED INJURIES IN THIS TRAGEDY pic.twitter.com/VN1nGP3PqE

— ?ThaKidKamora? LulBaybeee?BLM✊?✊?✊? (@iamkamilleamora) December 19, 2022

?#UPDATE: The turbulence sent some passengers flying out of their seats and at least one hit the ceiling The plane was carrying 278 passengers and 10 crew members pic.twitter.com/0LgdjEyO8d

— R A W S A L E R T S (@rawsalerts) December 19, 2022

One passenger, Jacie Hayata-Ano, spoke to CNN, describing the sensation of being lifted off her seat while buckled in: “It felt like free-falling.”

Heather Poole, author of Cruising Attitude: Tales of Crashpads, Crew Drama and Crazy Passengers, recently told the Telegraph that events like this are exactly why airlines want you to use your seatbelt for the duration of flights. “The reason you must wear a seat belt, flight crew included, is because you don’t want the plane coming down on you.”

Although it might feel like we’re lifting up during turbulence, the airplane is actually dropping, she explained. “It comes down hard and it comes down fast, and that’s how passengers get injured — by getting hit on the head by an airplane.”