CLARKSVILLE (AP) — A small Tennessee restaurant chain has been ordered to pay $563,350 in back wages to 120 employees after the U.S. Department of Labor found it violated minimum wage and overtime rules.

Don Pancho Mexican Restaurant kept a portion of servers' tips and paid other workers a flat salary regardless of how many hours they worked, according to a Friday news release from the Labor Department. Don Pancho also failed to record all of the hours employees worked, the investigation found.

In addition, the restaurant chain was fined $683 for violating child labor rules by allowing a 15-year-old to work outside of allowed hours and for more hours than allowed by law.

At the time of the violations, the chain operated restaurants in Ashland City, Mount Juliet and Jackson, according to the release. A message left at one of the restaurants by a reporter on Friday afternoon was not immediately returned.