Inspectors are due at a North Carolina amusement park Monday as they continue investigating a roller coaster shuttered since shortly after a dad spotted a crack at the top of one of its steel support pillars.

"I'm not an engineer, but that's not right," Jeremy Wagner thought Friday on his visit to the Carowinds park in Charlotte, he told CNN.

The Fury 325 will stay closed until inspections and repairs happen, park officials have said. It's one of the tallest and longest rides in a massive park that straddles the North and South Carolina state line.

Personnel with the state Department of Labor's Elevator and Amusement Device Bureau are due there Monday, spokeswoman Erin Wilson told CNN on Sunday. The agency didn't share anything else about the nature of its inquiry.

Wagner knew something was wrong when he spotted the aperture in the coaster's infrastructure, he told CNN. He pulled out his phone and hit record, zooming in on the crack to show the support pillar move slightly out place as passengers flew by.

"My daughter and niece rode it six times," he told CNN.

Wagner reported the incident to the park's guest services but still felt uneasy after he left, he said, "so, I called Charlotte Fire."

"They called me back within 10 minutes and advised the ride was shut down," he said.

Fury 325 is "the tallest, fastest, longest giga coaster in North America," with a peak height of 325 feet and reaching 95 mph, the park says. A "giga" roller coaster has a drop between 300 and 399 feet, according to Kings Island amusement park in Ohio.

The rest of the Carowinds amusement and water park is open Monday, its website says.

All rides, including Fury 325, "undergo daily inspections to ensure their proper functioning and structural integrity," Carowinds said.

"Safety is our top priority," it said, "and we appreciate the patience and understanding of our valued guests during this process."