UPDATE 5:20pm Sept. 22 — The man has been identified as Trevor Lee Nelson, as reported by Sheriff Wendt.
The investigation has reported that he was traveling northbound on Lower North Fork Road.
During a left-hand turn, the vehicle left the roadway to the right and overturned into a pond beside the road. The driver was trapped and pronounced dead at the scene.
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A 44-year-old Wisdom man was found dead Sunday (Sept. 21) after his vehicle flipped and became submerged up-side-down in water along Lower North Fork Road, according to the Beaverhead County Sheriff's Office.
Pictured: Vehicle submerged in water (credit: Beaverhead County Sheriff’s Office)

Authorities discovered the overturned vehicle around 10:37 a.m. with only the tires showing above the water surface. A deputy who responded to the scene observed that the driver's side door appeared to have been forced open, indicating a possible escape attempt.
Sheriff's deputies initially searched for the vehicle owner at his residence and workplace, but was not found. Sheriff Wendt returned to the scene and used chest waders and a safety rope to access the submerged car. He forced open the passenger door and found the man's body inside.
Photo credit: Beaverhead County Sheriff’s Office

Location of accident:

The victim was last seen the night before and remained trapped in the vehicle overnight, according to The Montana Highway Patrol, who is leading the investigation. The victim's name has not been disclosed, pending notification from family members.
Investigators believe alcohol played a role in the incident.
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