(Reuters) - Wal-Mart Stores Inc agreed to pay $4.8 million in back wages and damages to thousands of employees for unpaid overtime after a probe by the U.S. Department of Labor found that the retailer had violated a federal law governing overtime pay.

Wal-Mart will also pay $463,815 in civil fines.

According to the Labor Department, Wal-Mart failed to pay overtime to certain employees, considering them to be exempt from overtime requirements, when they were in fact not exempt.

Wal-Mart said it has already adjusted its pay practices, determining that back wages should be paid for 3,700 employees in two roles.

"When the issues resolved today were initially raised, we took them seriously and fully cooperated with the Department of Labor to make sure they were corrected in 2007," said Wal-Mart spokesman Greg Rossiter.

He said the settlement involved employees serving in the roles of Asset Protection Coordinator and Vision Center Manager. About 1700 employees in the former role are eligible for about $290 on average in back pay, Rossiter said, while some 2000 employees in the latter role are eligible for about $2300 on average.

Wal-Mart, the world's largest retailer, is facing allegations that it covered up bribery at its Mexican unit.

(Reporting by Martinne Geller in New York)