Family, friends, and fellow law enforcement officials are preparing to say goodbye to Deputy Robert "R.J." Leonard today as he will be laid to rest.

The body of the deputy, who was transporting a woman to the county jail last Wednesday, was discovered in the Tennessee River along with the woman and his car the next day.

Leonard, a rookie with the Meigs County Sheriff's Office, was reported missing Wednesday evening when dispatchers began their evening check-in with all deputies and officers on the road, according to The Tennessean, part of the USA TODAY NETWORK.

"Every deputy or officer that was out checked in and said they were OK, but not Deputy Leonard," District Attorney General Russell Johnson said at a press conference Thursday. "So, for the next several hours, as surrounding agencies learned what was going on, began responding to this area."

Given the Leonard had responded to an incident close to the river, the Tennessee Wildlife Resource Agency began a visual sweep of the water. His phone also pinged in the area of the river, said authorities.

Cellphone and tracking data eventually led responders to the area near a boat ramp, where officials said several other vehicles have rolled into the water, according to the Police Benevolent Foundation, who set up a memorial fund to help Leonard's family.

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Deputy R.J. Leonard's patrol car was found upside down with wheels up

On Thursday afternoon, authorities confirmed the vehicle in the water was Leonard's patrol car.

"The vehicle was nose in, but upside down, wheels up," Johnson said, adding that the trunk was blown open by the pressure.

Leonard was not found in the vehicle, but the driver's window seat was down. The woman, who Leonard had detained, was found in the backseat covered in "a lot of mud". She has not been publicly identified and no further information on her was made available.

The Meigs County Sheriff's Office could not immediately be reached for a clarification on where the deputy's body was found.

The Hamiton County Sheriff's Office later said that Leonard's remains were later transported the Knoxville Regional Medical Examiner’s Office. The cause of death has not yet been announced.

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What happened before Deputy R.J. Leonard went missing?

On Wednesday night, Leonard was called to a scene of disturbance near Birchwood Community, about 35 miles north of Chattanooga.

"Cell phone service in this neck of the woods is not good and radio communications are not as we've found out," Johnson said.

Johnson said that Leonard arrived at the scene at 9:48 p.m. and was on his way to the county jail three minutes later.

Shortly after, another communication took place.

"The next communication happened approximately 12 minutes later at 10:03 p.m.," Johnson said. "There was a radio communication that had come out and dispatch couldn't tell what he was saying."

However, investigators later analyzed that Leonard said "water" in the radio communication, based on voice analysis tools.

At the same time, Leonard's wife received a one-word text message that read "arrest," Johnson said. She responded to the text, though his phone never got the message.

Investigation ongoing into deaths of Deputy R.J. Leonard and woman he arrested

Johnson said that authorities would continue to investigate the incident to determine the cause of the accident.

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

Leonard has been part of the team for only two months, Meigs County Sheriff Brian Malone said in the press conference.

"He was doing a pretty good job. A really good job. It's just hard when the department is like a family," a tearful Malone said.

Leonard, 35, who was originally from New York, is survived by his wife Christa Leonard and their five children, his mother and two siblings, according to the Police Benevolent Foundation.

His funeral service will be held in Meigs County on Monday, Feb. 19 at 7 p.m. ET, as per his obituary.

Saman Shafiq is a trending news reporter for USA TODAY. Reach her at [email protected] and follow her on X, the platform formerly known as Twitter @saman_shafiq7.