Viafore, 46, disappeared while kayaking with his fiance, 35-year-old Angelika Graswald, on April 19.
Graswald is charged with second-degree murder in connection with Viafore's disappearance.
Forensic scientist Michael Archer, who is working for Graswald's defense team, said the body is Viafore's, but the medical examiner has not yet ruled officially, CBS2 reported.
An autopsy will be performed on Tuesday.
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