Searchers discovered a body in the Kennebec River in Richmond at approximately 3:10 p.m. Friday.

Authorities did not identify the body, which was taken to the Maine Medical Examiner’s Office. But searchers had spent most of the previous 20 hours searching for Mark Johnston, 64, of Richmond, who was reported missing at 9:21 p.m. Thursday.

A dive team recovered the body after shore and air searches that started Thursday night.

According to Marine Patrol reports, Johnston was planning to move his 32-foot recreational vessel from a mooring in Richmond to the Town Dock at approximately 6:15 p.m. Thursday. His boat was discovered aground on the west side of Swan Island a little more than four hours later.

The unoccupied boat was running and its navigation lights were on, according to a Maine Marine Patrol release.

Members of the local police department and the U.S. Coast Guard assisted the Maine Marine Patrol, which was leading the search.

Johnston was last seen on security camera footage arriving at the town dock at 6:11 p.m.

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