Thirty-five passengers were left with head and neck injuries after smashing against the roof of a plane during severe turbulence.
The incident happened on Air Canada flight 33 as it flew over the Pacific Ocean during a service from Vancouver to Sydney on Thursday.
The aircraft was forced to make an emergency landing at Daniel K. Inouye International Airport in Honolulu after encountering sudden "clear air" turbulence.
Pilots on the Boeing 777 aircraft decided to turn back after flying through the known turbulence hotspot.
One terrified passenger said oxygen masks fell from the ceiling during the incident.
Pictures taken inside the plane show panicked passengers surrounded by oxygen masks hanging from the ceiling.
In one of the photographs, emergency service workers can be seen aboard the flight and appear to be tending to a patient.
The plane had 269 passengers and 15 crew members onboard at the time and nine customers had to be taken to a nearby hospital for treatment to their injuries following landing.
Passenger Michael Bailey told Hawaii News Now: "It was pretty quick. And a lot of people hit the ceiling.
"A lot of screaming. In the seat in front of me, the girl hit her head, and actually snapped and broke it (the ceiling compartment).
"It was scary for a brief moment, and then the plane levelled out."
Passenger Tim Tricky told Montreal CTV News: "It started get a little bit rocky, so I thought I'd better buckle up, and then about five seconds later, you just watch everyone's head in a plane who wasn't wearing a seatbelt hit the roof like a jack-in-a-box.
"It was pretty scary to see. One of our band members, our mate, he smacked it really hard and put a massive dent in the luggage compartment."
The carrier's initial reports were of 25 people with minor injuries.
In a statement the airline said: "Our first priority is always the safety of our flights, passengers and crew and as a precaution, medical personnel are on standby to examine passengers in Honolulu.
"We are currently making arrangements for the passengers including hotel accommodations and meals in Honolulu, as well as options for resumption of the flight."
A case of severe turbulence in June on a flight from Kosovo to France was captured on video, showing a flight attendant hitting the ceiling and another praying.
In another case, 29 people were injured after a Turkish Airlines flight encountered severe turbulence on its approach to New York's John F. Kennedy International Airport in March.
