In Kansas City, Missouri, what was meant to be an exhilarating experience at Worlds of Fun transformed into a frightening ordeal for some visitors.

On October 11, a couple recounted their unnerving ride on the Mamba, the theme park’s tallest roller coaster, when they heard a young girl seated behind them exclaim that her seat belt was not fastened.

“It was completely unbuckled,” Chris Evins recalled, as he assisted in securing the girl. “There was a significant gap between her and the safety bar.”

Throughout the 205-foot plummet, Evins and his wife took it upon themselves to firmly grip the girl and her companion seated nearby.

“I assured her, ‘We’ll see you safely through the remainder of this ride. We’ve got you,'” Evins recounted.

According to Cassie Evins, both girls were visibly distressed, holding on tightly as tears streamed down their faces.

“72 miles an hour, holding onto somebody. It’s terrifying,” Cassie Evins said.

One day after that incident, a guest reported another alleged seat belt malfunction on the Mamba.

A mother said she shouted that her son’s seat belt hadn’t locked as the cars entered their first climb.

This time, the ride reportedly stopped, and the seat belt, which the mother said was twisted and loose, was adjusted.

“We probably won’t go back for a while,” Cassie Evins said. “We need to see the change, and once we see that change, I will be comfortable taking my four children, who I am not comfortable taking currently.”

Inspectors from the Missouri Division of Fire Safety reportedly went to evaluate the coaster Thursday morning.

They told one of the affected guests that a ride inspector discovered some restraint devices that were “not functioning properly” on the Mamba, and the ride was taken out of service until repairs were made, which were expected to be done Thursday or Friday.

KMBC 9 reached out to Six Flags, the parent company of Worlds of Fun, for a statement on the situation.

“The safety of our guests and team members is a top priority,” a park spokesperson said. “Following the report of a guest concern on the ride earlier this month, our team immediately closed the ride and completed a thorough inspection before reopening it that evening. The ride is equipped with a multi-layered restraint system, and it has operated safely since the initial concern was raised.

“The ride has undergone a comprehensive safety review, and we have implemented modifications requested by the Fire Marshall to ensure it meets or exceeds all applicable safety standards before it reopens to guests this evening.”

This story was provided to CNN Wire by an affiliate partner and does not contain original CNN reporting.