The 1995 green Dodge Ram pickup truck was found at Harriman State Park around 1 p.m. on Tuesday afternoon.
However, 73-year-old Eugene Palmer was not with the vehicle. Authorities were searching the park for the experienced outdoorsman, using tracking dogs.
Palmer allegedly shot his daughter-in-law in a fit of rage on Monday. Tammy Palmer, 39, lived in a neighboring house on the Palmer property in the town of Haverstraw.
The victims' parents told Eyewitness News the shooting stemmed from a long simmering marital dispute between Tammy Palmer and her estranged husband, John, who no longer lives on the family property.
Police say Tammy Palmer's body was found behind her house at 7:40 on Monday morning. Investigators say she was shot with a rifle or shotgun. Her two teenage children were in school at the time of the shooting.
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