Transcript for Ride Called Vortex at North Carolina State Fair Sends Five to Hospital.
And now, to the thrill ride gone wrong at the state fair in north carolina. Riders thrown to the ground by a ride that spins and flips upside down. The ride was supposed to be over, when some were knocked unconscious. Abc's david kerley has the latest on what happened. Reporter: Tonight, the chaotic 911 calls. You got to get somebody out here quick, on the vortex ride. Reporter: The vortex ride at the north carolina state fair. Is there any serious bleeding? Yes, they are bleeding. Reporter: These pictures right after the carnival ride accident. There is like one, two, three, four, five people down. Reporter: First responders arrived within minutes two critically hurt. In all five were taken to the hospital. Two people have gone home. They were riding the vortex. This is it in operation right before the accident. It spins, twists and turns upside down. But as riders were unloading, it suddenly started up again, slamming a worker and riders to the metal deck. How does one get critical injuries with what happened last night? Can you tell us specifically what happened. It's like a car wreck. Cars break down, cars wreck. I don't know how they got -- each one was hurt. Reporter: The association that represents carnival operators tells us americans take more than a billion rides a year, and each year, 13,000 are injured and visit an emergency room. That is a higher rate than at theme parks, which have many more riders, and fewer injuries. There was a switch problem, that was fixed on that vortex ride on monday. But officials don't know if it's related to the accident. Which they are calling an isolated incidents with two people with critical injuries this vortex ride is shut down for the last busy weekend of the north carolina state fair.
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