The U.S. Department of Labor has ordered the operator of four New Jersey Dairy Queen franchises to forfeit nearly $24,000 after it found the locations violated minimum wage and child labor regulations.

The franchisee who operates Dairy Queen locations in Rutherford, West Milford, Emerson and Belmar, must pay $14,006 in civil penalties and $9,764 in back wages to the employees affected, the department said Monday.

Investigators with the department's Wage and Hour Division determined the franchisee failed to pay one worker minimum wage and did not pay 14 workers the required time-and-a-half overtime rate for working more than 40 hours per week.

The franchisee was also found to have employed 15-year-old workers for longer and later hours than allowable under the Fair Labor Standards Act. The violations affected 23 minors across the four Dairy Queen locations.

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"Fast-food franchises like Dairy Queen offer minor-aged workers valuable work experience, but federal law ensures that experience does not come at the expense of a young worker’s education or related activities," said Paula Ruffin, North Jersey district director of the Wage and Hour Division office in Mountainside.

The Fair Labor Standards Act prohibits 14- and 15-year-olds from working past 9 p.m. from June 1 through Labor Day and past 7 p.m. the rest of the year. In addition, they are not allowed to work more than three hours on a school day, eight hours on a non-school day, 18 hours per week when school is in session and 40 hours per week when school is not in session.

The division found that 15-year-old Dairy Queen employees exceeded the daily and weekly maximum work hours during the school year and sometimes worked as late as 10 p.m.