Updated

Witnesses described a horrific scene of children on a collapsing carnival swing ride being slammed into the ground and the side of the ride.

The incident Friday night at the Calaveras County Fair in the northern California community of Angels Camp injured 23 people, mostly children, and now state safety inspectors are trying to find out what caused the nightmare scene.

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"It dropped down and dragged the kids around in circles," Phillip Coulson, whose godson was on the ride, told KTXL-TV in 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, told the Union Democrat 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," she told the newspaper.

Click here for the story from KTXL-TV.

Click here for the story from the Union Democrat.

The ride, called the Yo-Yo, collapsed shortly after 6 p.m. Friday at the fair, which features the famous Jumping Frog Jubilee. The fair remained open after the accident, but the carnival area was shut down.

"This was a traumatic accident. It wasn't something that any of us expected," said Ray Malerbi, CEO of the Calaveras County Fair. "Our first concern is for the people that were hurt."

All but one of the injured patrons sent to area hospitals for treatment had been released Saturday, Malerbi said.

Inspectors from the California Occupational Safety and Health Administration began arriving late Friday and early Saturday to investigate the accident and inspect all the carnival rides.

Most of the rides were expected to reopen Saturday after OSHA officials finished inspecting them, but the Yo-Yo will stay closed while officials investigate the accident, Malerbi said.

OSHA officials did not immediately respond to a call for comment.

The Yo-Yo ride has a series of metal arms extending from a center poll. A chair is attached to the end of each arm by a chain, and the arms and chairs swing outward as the machine spins and picks up speed.

The accident occurred when all of the arms and chairs suddenly collapsed, dragging the passengers on the ground until the machine finally came to a half, according to witnesses.

All the carnival rides, including the Yo-Yo, are owned and operated by Oroville-based Brass Ring Amusements, which has never been cited by state safety inspectors, said owner Harry Mason.

"In 31 years in the business, I have never seen anything like this before. This is just absolutely sickening to me," Mason said. "My concern first and foremost is the children. My children ride my rides."

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.

Last year's jumping frog contest drew 4,000 entries. This year's final is scheduled for Sunday.