The U.S. Department of Labor said on Tuesday that its investigators had discovered two 10-year-old children working in the kitchen at a Louisville McDonald’s restaurant.

They were employed—but not paid—by Bauer Food LLC, a Louisville-based operator of 10 McDonald’s locations, officials said, and sometimes worked as late as 2 a.m. preparing and distributing orders, cleaning the store, working the drive-thru window, and operating cash registers.

One of the two children was allowed to operate a deep fryer, which is banned by law for workers under the age of 16.

Children below age 14 are generally not permitted to work in any capacity under federal law, and those ages 14 to 15 have limits on the number of hours they can work, particularly on school days.

“Under no circumstances should there ever be a 10-year-old child working in a fast-food kitchen around hot grills, ovens, and deep fryers,” Karen Garnett-Civils, the Labor Department’s wage and hour division district director in Louisville, said in a statement.

305 minors

The two 10-year-olds were among 305 minors found to be working more than the legally permitted hours across 62 McDonald’s locations in Kentucky, Maryland, Indiana, and Ohio.

The restaurants were operated by three franchisees: Bauer Food, Archways Richwood LLC, and Bell Restaurant Group I LLC, according to the Labor Department.

Bauer Food employed a total of 24 children under the age of 16 to work longer hours than legally allowed, while Archways Richwood had 242 minors working beyond the allowable hours, and Bell Restaurant Group allowed 39 children to work longer than permitted, the Labor Department’s investigations found.

Collectively, they were fined $212,544 for violating child labor laws.

Bauer Food said the 10-year-olds found working at its locations were the children of a night manager who were visiting their parent at work. The company said the children had not been approved by management to be working in the restaurant, and that it had taken steps to make it clear to staff what policies were in place around children visiting their parents or guardians at work.

Tiffanie Boyd, senior vice president and chief people officer at McDonald’s USA, said in an emailed statement on Thursday that the reports were “unacceptable” and “deeply troubling.”

“It is not lost on us the significant responsibility we carry to ensure a positive and safe experience for everyone under the Arches. I know how important it is that every restaurant fosters a culture of safety,” she said. “As a mother whose teenage son proudly worked at our local McDonald’s, I feel this on a very personal level. We are committed to ensuring our franchisees have the resources they need to foster safe workplaces for all employees and maintain compliance with all labor laws.”

Archways Richwood and Bell Restaurant did not respond to Fortune’s requests for comment.

The Labor Department found 688 minors employed illegally in hazardous occupations in 2022—the highest number since 2011. Among them was a 15-year-old who was injured while operating a deep fryer at a McDonald’s in Morristown, Tenn., in June.

“We are seeing an increase in federal child labor violations, including allowing minors to operate equipment or handle types of work that endangers them or employs them for more hours or later in the day than federal law allows,” Garnett-Civils said. “An employer who hires young workers must know the rules.”

The Labor Department’s investigation findings come as Republican lawmakers in several states are seeking to relax child labor laws.

On Wednesday, Iowa’s legislature passed a bill led by GOP lawmakers that would reduce child labor protections, including the limit on the number of hours teenagers in school are allowed to work. It would also allow minors to work in occupations they are currently not permitted to fill, such as meat processing, operating heavy machinery, and serving alcohol.

The bill would come into effect if signed by Gov. Kim Reynolds, who has expressed support for the proposed changes.

Lawmakers in Arkansas, Missouri, Ohio, and Wisconsin have also floated the possibility of easing laws around child labor.