MISSION, Texas -- Local authorities said the region's largest chain of car dealerships lost at least $500,000 to a theft scheme led by some of its managers, reported the Valley Morning Star newspaper.

Hidalgo County Sheriff Lupe Treviño said the alleged theft, discovered earlier this month by internal auditors at the Bert Ogden family of dealerships, could result in criminal charges for at least three longtime employees and a significant financial hit to the company.

"Half a million dollars is a very conservative estimate," the sheriff said. "But as far as we can tell, no customer was directly affected. Nobody got hurt except Bert Ogden."

Bert Ogden owner and chief executive officer Robert Vacker declined interview requests, but said in a written statement that the case "in no way affected customers who have purchased from the store."

According to court affidavits filed to obtain a search warrant, officials suspect Fabian Leal, 45, Javier Lopez, 45, and Rene Deleon, 54 - all of whom worked at the Bert Ogden Chevrolet dealership in Mission - defrauded the company over a period of at least three years.

Officials said they suspect the men of filing hundreds of vouchers for contract work that was never done. Officials said each of the service orders was billed from a Mission-based company, which claimed it had installed more than 800 aftermarket dash kits for vehicles later sold at the dealership.

Officials said the case came to light when a Bert Ogden service center employee discovered a car that should have had a custom-installed audio system only had the standard factory-installed system.

When asked about the irregularities, Deleon, the dealership's aftermarket manager at the time, resigned immediately, according to court affidavits filed in the case. Leal, the general sales manager, and Lopez, who worked as the new-car manager, were fired, officials said.

"We're looking at hundreds and hundreds and hundreds of vouchers," Treviño said. "This is one of those cases that is going to be very labor intensive and take a while."

None of the men have been charged with a criminal offense. It was unclear whether any had retained an attorney. Calls to phone numbers listed in their names were not returned.