At least two Transportation Security Administration officers at Dallas-Fort Worth International Airport have been arrested in a police sting operation involving stolen parking passes and dozens of others could be in trouble, NBC 5 has learned.

Sources familiar with the probe said it started several months ago with an undercover investigation by the airport's Department of Public Safety.

Investigators found an American Eagle worker had stolen 100 parking passes for employee parking lots and recruited TSA officers to sell the passes to co-workers for $100 apiece, the sources said.

One person who was aware of the investigation said as many as 20 TSA officers are suspected of selling or buying the passes. Another person said the number was closer to 40.

It was not immediately clear whether or not the airline employee also had been arrested.

TSA spokeswoman Carrie Harmon initially referred questions to airport officials, though the agency released a statement Friday afternoon saying they are cooperating with the investigation and that they do not tolerate any form of unlawful behavior and that eight employees have been placed on indefinite suspension without pay.

On Friday afternoon, officials with American Eagle issued a similar statement:

"American Eagle has a zero-tolerance policy for this type of activity. We have worked closely with the DFW Airport Department of Public Safety to investigate this matter. The individual involved is no longer employed by American Eagle."

DFW Airport spokesman David Magana declined to comment on the investigation or confirm any arrests.

TSA officers at DFW Airport -- even part-time -- are required to pay $102 every quarter to park in two employee parking lots. The stolen airline parking passes allegedly sold for $100 allowed employees to park for one year.

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