Police went to the Martins' home Saturday after relatives became concerned when the men failed to show up for a Thanksgiving dinner the day before. A neighbor told them that a vehicle owned by Lester Martin was hidden in the woods near the back of the property.
Police now say the younger Martin killed his father a week earlier and hid the body.
He was arrested Sunday and arraigned in the town of Wallkill.
Martin, who is 57, is being held Monday in the Orange County jail without bail. Court officials say they don't know if he has a lawyer.