The U.S. Department of Labor ordered a popular Pompano Beach restaurant to pay its 31 workers $732,976 in back pay after they were found to have worked overtime without compensation.

The department’s Wages and Hours Division investigates anonymous complaints without disclosing the reason to the employer, according to the Labor Department’s website.

The restaurant, Miyako Japanese Buffet, at 1157 S. Federal Highway in Pompano Beach, was found to have paid most employees a monthly salary between $1,000 to $3,000, even though employees typically worked more than 40 hours per week.

“The department’s Wage and Hour Division investigators determined the employer also failed to pay minimum wage for all hours worked and maintain required records, all in violation of the Fair Labor Standards Act,” the agency stated in a news release.

The restaurant did not properly keep track of how many hours each employee worked, the agency found.

A manager at the restaurant declined to comment Friday afternoon, promising to relay the request for comment to the owner.

Rafael Olmeda can be reached at rolmeda@sunsentinel.com or 954-356-4457.