One adult and two children were hurt when a wheel-bearing seized on one of the cars causing a rear-end collision between three cars on the Zyclon roller coaster.
"When the wheel froze up, the bearing froze, it caused that individual car to slow down and when it did, it was impacted from the rear by another car," State Fair Spokesman James Knight said.
Delma Newsome was on the car in the rear.
"It was so fast. I saw it coming but we were going so fast," Newsome said. "It happened quick and it was just a shock."
Newsome said she and her daughter were jolted into a bar in the front of the car, injuring their mouths, chins, necks and backs.
The Newsomes and another person were immediately taken to the hospital.
The ride was stopped while state officials inspected all the cars.
Newsome is not convinced that the accident was all a mechanical error. She placed part of the blame on a worker at the ride who she said could have pulled a lever to slow her car down.
"He should have been able to stop us and he didn't," Newsome said.
Fair officials said there was no evidence of wrong-doing on anyone's part, and the ride operator said state inspectors have deemed the Zyclon safe.
The ride re-opened within an hour on Saturday, and no problems were reported on Sunday.
Fair officials said they have asked inspectors to pay particular attention to similar rides to prevent this problem from happening again.