CLARKSVILLE, Tenn. -- Det. Raymond Macias has been suspended from the Clarksville Police Department pending a criminal investigation from the Tennessee Bureau of Investigation. The investigation, which was opened last week, concerns possible illegal use of prescription drugs.

Video: TBI Investigates Clarksville Narcotics Officer

The narcotics agent was put on paid leave as of Friday. He has not been arrested, but the investigation is ongoing.

"No one else is involved, just him. No one else is involved at the police department," said Police Chief Al Ansley, who said he's never had problems with Macias before.

"I've known Ray for 23 years. I was actually in the academy with him, and I have a great deal of respect for him," Ansley said. "He is a friend of mine, and I've never had any difficulty with Ray Macias."

The Macias family said they would like privacy and request prayers during this time pending the outcome of the investigation.

It's unclear at this point whether the investigation will affect any of Macias' current cases.

Macias has been with the department for 23 years. For the last 19 years, he's worked in narcotics.

"He investigates any drug activity, basically, is what he does," said Ansley.