Law enforcement officials say Dr. David Landseadel, 48, was found near Stinson Lake in Rumney Sunday evening.
An autopsy determined Landseadel died from a single gunshot wound to the head. Investigators say the cause of death has bene ruled a homicide.
"The investigation thus far has revealed that the victim's death arose from an altercation he had with another male individual who was known to him," according to a press release from the state attorney general's office. "The circumstances surrounding this altercation, any prior contacts between the victim and the other male are the subject of the ongoing investigation."
No arrests have been made, according to the state attorney general's office.