DENVER (CBS4) – A CBS4 investigation has learned that two Transportation Security Administration screeners at Denver International Airport have been fired after they were discovered manipulating passenger screening systems to allow a male TSA employee to fondle the genital areas of attractive male passengers.

It happened roughly a dozen times, according to information gathered by CBS4.

According to law enforcement reports obtained during the CBS4 investigation, a male TSA screener told a female colleague in 2014 that he “gropes” male passengers who come through the screening area at DIA.

“He related that when a male he finds attractive comes to be screened by the scanning machine he will alert another TSA screener to indicate to the scanning computer that the party being screened is a female. When the screener does this, the scanning machine will indicate an anomaly in the genital area and this allows (the male TSA screener) to conduct a pat-down search of that area.”

Although the TSA learned of the accusation on Nov. 18, 2014 via an anonymous tip from one of the agency’s own employees, reports show that it would be nearly three months before anything was done.

RELATED: TSA, Denver Refuse To Release Groping Video, Reports

On Feb. 9 TSA security supervisor Chris Higgins watched the screening area, observing the employees. “At about 0925 he observed (the male TSA screener) appear to give a signal to another screener … (the second female screener) was responsible for the touchscreen system that controls whether or not the scanning machine alerts to gender- specific anomalies, according to a law enforcement report obtained by CBS4.

DOCUMENT: Read The Police Report

According to the report, the TSA investigator then watched a male passenger enter the scanner at DIA “and observed (the female TSA agent) press the screening button for a female. The scanner alerted to an anomaly, and Higgins observed (the male TSA screener) conduct a pat down of the passenger’s front groin and buttocks area with the palm of his hands, which is contradictory to TSA searching policy.”

Higgins later interviewed the female TSA agent who was an accomplice in the groping conspiracy. She “admitted that she has done this for (the male TSA officer) at least 10 other times. She knew that doing so would allow (the male TSA officer) to perform a pat down on a male passenger that (the male TSA screener) found attractive,” reported Higgins.

The TSA said the male passenger who they saw being fondled was flying on Southwest Airlines and the agency has videotape of the incident. CBS4 has requested the tape but it was not immediately released. TSA has said it could not identify the male passenger who was groped and the agency says there have been no other complaints about the serial groping.

A spokesperson for TSA released a brief written statement to CBS4 saying, “These alleged acts are egregious and intolerable. TSA has removed the two officers from the agency. All allegations of misconduct are thoroughly investigated by the agency. And when substantiated, employees are held accountable.”

The agency has not released the names of the two fired employees and refused a CBS4 request for an interview.

Earlier this month a prosecutor from the Denver District Attorney’s Office was asked to review the case but she declined to press charges because there was no reasonable likelihood of conviction and no victim had been identified.

It’s not the first time TSA screeners at DIA have been accused of inappropriate touching of passengers. Jamelyn Steenhoek filed a complaint against TSA screeners at the airport saying the frisking she received in December 2013 amounted to a sexual assault. She said a female TSA agent searched her at an airport checkpoint after an alarm went off.

“There are just areas of my body I’m not comfortable being touched in. On the outside of my pants she cupped my crotch,” said Steenhoek, who called the frisking “invasive.”

She said “the part of the search that bothered most was the breast search. You could tell it shouldn’t take that much groping. I felt uncomfortable, I felt violated.”

In 2014 the Denver District Attorney’s Office announced it would not be filing criminal charges in the Steenhoek case.

RELATED: TSA, Denver Refuse To Release Groping Video, Reports

Across the country other passengers have raised concerns over the years about TSA pat downs. But the recent case uncovered by CBS4 is more problematic for TSA since its own employee blew the whistle on the practice, a supervisor observed it happening, the agency fired the employees, and the female screener who was fired admitted to the fondling conspiracy.

CBS4 Investigator Brian Maass has been with the station more than 30 years uncovering waste, fraud and corruption. Follow him on Twitter @Briancbs4.