The Fort Campbell soldier reported missing at Kentucky Lake on Friday was found dead in the lake Monday, officials said.
Lyon County Judge-Executive Wade White said divers found the man beneath the surface at about 8 a.m.
The soldier has been identified on social media and in other reports as JuWan Richardson of Gordon, Alabama.
White said Richardson was found in an area where the water is about 20 feet deep.
Richardson had been reported missing shortly before 5 p.m. Friday. He had been tubing and was last seen at Mile Marker 30 near Lake City.
White said rescue teams from across the area, including Lyon, Marshall, McCracken, Trigg, Calloway and Graves counties, responded to help with the search.
"He was found in the area where they said they saw him go down last," White said. "It just took awhile to pinpoint exactly where it was."
Fort Campbell public affairs officials did not confirm the soldier's name Monday, citing the need to officially offer condolences to family members.
Richardson's body was taken to the Lyon County Coroner's office.
Deputy coroner Kris Dunn said the State Medical Examiner's Office was performing an autopsy Monday afternoon.
Dunn said preliminary notes could be available today, but full findings of the autopsy could take longer than a month to release.
White said many other area residents, including fishermen, had volunteered to aid in the search.
"We consider any of our soldiers at Fort Campbell, they're family to us," White said. "They volunteer to serve our country. We weren't going to stop until we were able to locate him."
White said he had spoken with Richardson's family during and after the search.
"They're very thankful for all of the volunteers who stayed at it, who sweated and worked and did everything they could to locate the victim," he said, adding the agencies worked seamlessly together.
"I'm very proud of these organizations. The majority of them, if not all of them, are volunteers. They have jobs and they have families, and they gave up their whole weekend in order to do that," White said.
He also stressed the importance of water safety for anyone enjoying the lake -- particularly the need to wear a life jacket.
White said Richardson was found without one.
"We want people to come down here and enjoy these beautiful lakes, but we want them to be safe," he said, asking guests not to underestimate risks in the water.
"You never know what may happen. It's tragic when it does happen."