McMINNVILLE, Tenn. -- A fourth police officer is out of a job following a raid at a McMinnville Americare Walk-In Clinic. State investigators believe prescription drugs were being illegally sold out of the clinic.

The Channel Four I-Team has also obtained documents that may finally show how officers are linked to the case.

Deputy David Seibers became the fourth officer in the past two weeks that has either resigned or been fired in the wake of the raid at the Americare clinic in McMinnville.

In his resignation letter to Warren County Sheriff Jackie Matheny, obtained by the Channel 4 I-Team, Seibers writes, "Over the past week, I have cried more than I think I have ever cried in my 32 years of life … It saddens me that I let a personal affliction get in the way of my family and my career."

Seibers doesn't explain his affliction, but in the search warrant and affidavit -- obtained by the I-Team before a judge sealed the case -- agents detail how prescription drugs were sold out of the Americare clinic illegally.

The documents detail how Tennessee Bureau of Investigation agents, using an undercover informant, were able to obtain hydrocodone and lortab without a prescription.

It is unclear if Seibers' "affliction" had anything to do with prescription drugs.

But it is clear how close he was to Matheny, writing that he resigns "with the deepest reluctance, but knowing it's what's best for the department, and, hindsight, me."

At the time of the raid, Matheny told the I-Team how difficult it was to have one of his deputies under investigation.

"When you work together in our profession, you become like family than coworkers," he said. "It kind of hurts, you know?"

Seibers could not be reached Tuesday for comment.

No one has been arrested or charged in this case.