A Toronto-bound Air Canada flight from Shanghai was diverted to Calgary on Wednesday, when the airplane encountered violent turbulence that had passengers describing the scene as a terrifying roller coaster ride, according to CBC News.

"It was the flight from hell," said passenger Connie Gelber. "We thought we were dying."

After the plane landed, passengers were taken through the terminal on stretchers and wheelchairs to waiting ambulances. Emergency officials said 21 people, including three children, were taken to hospitals with injuries ranging from minor sprains to serious chest and neck trauma. However, no one suffered life-threatening injuries, according to The Toronto Star. 

One flight 88 passenger, an artist who goes by Zarum, said the turbulence began when the plane was near Dawson City. 

"I was laying flat in a business class seat, I had my seatbelt on and suddenly I saw the passenger in front of me go flying up in the air, literally to the ceiling, and then hitting the ground again," Zarum said. "And then passengers started screaming and objects started flying. It lasted maybe half an hour."

Fifteen ambulances were dispatched to the scene as Emergency Medical Services enacted its mass casualty protocol, according to CBC News.

With Toronto being 2,200 miles away from Calgary, the airline said it would be making arrangements to accommodate all the passengers, and that the incident was being investigated, according to The Daily Mail.

Passenger Gord Murray commended the crew for their work. "It was a little scary, but all the crew were professional, handled themselves well," he said, according to CBC News. "It could have been much worse."

Another passenger, Bing Feng, said she was thinking of her family. "When you are in the situation, of course (you fear the worst). You saw all the oxygen masks drop," she said.