SAN ANTONIO – Three sergeants and one patrol deputy with the Bexar County Sheriff's Office are facing termination Thursday after they were accused of engaging in sexual activity on the job.

Two of the sergeants have already turned in their badges and guns and have been placed on administrative leave. The third sergeant and deputy have not yet received a formal notification, the Sheriff's Office said, because they have not answered their phones.

The case stems from allegations made five months ago that a lieutenant and patrol deputy engaged in sexual activity in a patrol vehicle while on the job.

Shortly after that, an investigation started into what sources have described as a "swingers club."

On Thursday, the Sheriff's Office moved to fire the four employees for "inappropriate behavior."

The lieutenant, Phil Dreyer, handed in a resignation letter when he was questioned in October, saying, "This will end my 37 1/2 years of service to the citizens of Bexar County and the state of Texas."

While Dreyer is no longer a Sheriff's Office employee, his resignation did not put an end to the investigation. The case has been handed over to the District Attorney's Office.

The four employees fired Thursday can appeal their terminations.