A sheriff’s deputy and a woman he arrested have both been found dead after officials say the officer accidentally drove his patrol car into the Tennessee River.

Robert J. Leonard, a deputy with the Meigs County Sheriff’s Office, made a radio call Wednesday saying he was returning to the local jail with someone he had arrested, District Attorney Russell Johnson said at a Thursday news conference. After making the call, Leonard didn’t respond to a status check from dispatchers. The deputy made one last radio call saying “water,” shortly after sending his wife a text message telling her about the arrest, according to Johnson.

A dive team found Leonard’s vehicle in the river during a search along a bridge at the deputy’s last known location, Johnson said. Once the vehicle was removed from the water Thursday, investigators found the body of Tabitha Smith, the woman Leonard had arrested, covered in mud in the back seat, while the driver’s seat was empty.

On Thursday night, the Hamilton County Sheriff’s Office reported Leonard’s body had been found.

The district attorney said he believes the deaths were accidental and explained the deputy wasn’t familiar with the area.

“We’re operating under the theory that it was an accident. He missed his turn,” Johnson said Thursday. “He wasn’t familiar and he was doing other things that may have caused him to go underwater. There’s skid marks and some scratch marks too. So there’s some indication that he was on the brakes, at least trying to stop … So it sounds like, you know, just an unfortunate accident.”

Meigs County Sheriff’s Office Chief Deputy Brian Malone said Leonard, who was from New York, had only been with the sheriff’s office since December.

On Monday, the Knox County Medical Examiner confirmed to CNN the female in the back seat of the car was identified as Smith.

It was not immediately clear what charges Smith was being detained on.

Friends remembered her as a happy and outgoing 35-year-old mother who often went by “Tabby,” according to CNN affiliate WVLT.

“She was a happy person, outgoing, she loved life,” Smith’s friend Sheena McHone told WVLT.

“I could not imagine being trapped and knowing my life was going to end,” said McHone.

McHone told CNN that Smith had four children – a boy and three girls.

Smith’s friend Emilie Neusel said she had “a heart of gold, and despite any struggles and troubles she had, she was a great person,” according to WVLT.

“I hope they remember her by her name. Tabby Smith,” Neusel went on. “And I hope she’s remembered by more than (being) the girl in the back seat.”

The Hamilton County Sheriff’s Office announced on Facebook there will be a funeral procession for Leonard on Tuesday.