Police say Petterson was last seen on Vancouver Island, in the Port Alberni area in June 1996, after telling his wife that he would be staying in Courtenay while looking for retirement property.
Police say there have been various sightings of Petterson on Vancouver Island ever since the man was reported missing, but none of the reports have been confirmed.
His family says he was a devoted husband and grandfather, he has no history of depression or suicidal tendencies, and he would never have intentionally left his family.
Petterson, who was three years away from retiring when he disappeared, has three children and would now be 74 years old now.
Police say Petterson's wife of more than 30 years died two years ago, not knowing what happened to her husband.
The man is described as Caucasian, and was 5'11, weighed 178 pounds, and had a light complexion, brown hair and blue eyes at the time of the disappearance.
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