NORTH MANKATO (AP) -- A truck service shop in North Mankato is contesting federal fines levied after a natural gas explosion last November that injured two workers.

The explosion happened Nov. 14 at Allstate Peterbilt when natural gas that leaked from a garbage truck ignited.

A 59-year-old Ellendale man was taken by helicopter to Regions Hospital in St. Paul with first- and second-degree burns. A 41-year-old Gibbon man injured his hand and was treated at the scene.

The federal Occupational Safety and Health Administration fined the business $14,000 for safety violations after an investigation. The truck shop's parent company, Allstate Sales and Leasing Corp., is contesting the penalties.