At least 35 people injured as Air Canada flight headed to Australia forced to make emergency landing in Hawaii.

Intense turbulence struck an Air Canada flight to Australia on Thursday and sent unbuckled passengers flying into the ceiling, leaving dozens with minor injuries and forcing the plane to land in Hawaii.

The flight from Vancouver to Sydney encountered “unforecasted and sudden turbulence,” about two hours past Hawaii when the plane diverted to Honolulu, leaving approximately 35 people with minor injuries, Air Canada spokeswoman Angela Mah said in a statement.

“The plane just dropped,” passenger Stephanie Beam told The Associated Press news agency. “When we hit turbulence, I woke up and looked over to make sure my kids were buckled. The next thing I knew there’s just literally bodies on the ceiling of the plane.”

A woman behind her hit the ceiling so hard that she broke the casing of an oxygen mask, said Beam, of Colorado, US.

Emergency responders met the plane at the gate. Honolulu Emergency Services Department spokeswoman Shayne Enright said injuries included cuts, bumps, bruises, neck pain and back pain. More than two dozen people were taken to hospitals, she said.

“I watched a whole bunch of people hit the ceiling of the plane,” said another passenger Alex MacDonald. “A couple of the air hostesses were bringing food out at the time, and they hit the roof as well.”

Passenger Luke Wheeldon told Honolulu news station KTIV about half the passengers weren’t wearing seatbelts.

“There was no warning and then half of them, their head hit the roof all at once,” he said. “And I went, ‘Oh, this is a bad day.’”

Babies and children were crying as crew members went through the cabin assessing injuries. About 15 minutes later, there was an announcement asking for passengers who are medical professionals to help, Beam said.

The turbulence happened at 36,000 feet (10,973 metres) about 966km southwest of Honolulu, said US Federal Aviation Administration spokesman Ian Gregor.

The Boeing 777-200 was carrying 269 passengers and 15 crew members, according to Air Canada spokesman Peter Fitzpatrick.

Air Canada was arranging hotel accommodations and meals in Honolulu and options for resuming the flight.