A parent’s worst nightmare came true on Friday night at the Calaveras County Fair and Jumping Frog Jubilee in California.
Onlookers helplessly watched as the Yo-Yo attraction spiraled out of control, sending riders, most of them children, flying through the air and injuring all 23.
The Yo-Yo ride, with a spinning base and mechanical arms, uses chains to lift riders in swinging seats off the ground.
"It dropped down and dragged the kids around in circles," Phillip Coulson, whose godson was on the ride, told KTXL-TV in Sacramento, about 80 miles southeast of the annual fair. "Two girls got hurt and my godson, he just scraped his knees."
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Some of the victims were thrown through the air as chains snapped, and three riders were airlifted to hospitals in Modesto and Sacramento.
Sean Ranney, who had exited the ride right before it crashed, described the scene to the Union Democrat.
"We just saw people bouncing off the ground and hitting the ride," he said. "It happened three times. It bounced, bounced and bounced, then people started hitting the ground."
Another witness, Cassidy Dean, 18, said in the Union Democrat story that she had been standing at the base of the ride when it went out of control.
"I just saw all these little kids smashed into the ground."
Investigators were trying to determine if the accident was caused by mechanical or human error, and workers reportedly were being tested to determine if drugs may have played a role, KTXL-TV reported.
The carnival rides remained closed, but the festivities continued as police investigated.
The ride is operated by Midway of Fun, which fair officials said they have worked with for 20 years, all without incident, KTXL-TV reported.
The ride has metal arms, each with a seat at the end attached by a chain, that swing outward as the ride picks up speed. The arms rise and fall as they spin around a center pole, putting the seats horizontal to the ground.
The pole apparently collapsed, causing the arms to crash back toward the center, said Dennis Townsend, a chief in the Calaveras County unit of the California Department of Forestry and Fire Prevention.
"The mechanism that lifts the people is the one that collapsed," he said.
The riders were hurt when their seats struck the ground or other parts of the machine, he said. Authorities could not immediately determine what might have caused the accident.
He did not know whether anyone on the ground was injured.
The Calaveras County Fair and Jumping Frog Jubilee opened Wednesday and is held each year in late May. It was inspired by a Mark Twain story, "The Celebrated Jumping Frog of Calaveras County," which focuses on a character and his jumping frog, named Dan'l Webster.
The fictional frog-jumping contest is rigged in one gambler's favor when he secretly fills his opponent's frog with buckshot.
The Calaveras County fairgrounds is just outside the Gold Rush-era town of Angels Camp in the Sierra Nevada foothills. It bills itself as an "old-fashion county fair" with exhibits and a variety of entertainment.
Last year's jumping frog contest drew 4,000 entries. This year's final is scheduled for Sunday.
The Associated Press contributed to this report.