Details of Disappearance
Duncan, John Porter, and another man, 42-year-old Cleburn Hammack, from Washita County, Oklahoma on April 8, 1969. Photos of Hammack are unavailable.
In 2014, the vehicle the trio was riding in was found in Foss Lake with three bodies inside. The bodies were identified as Duncan, Porter and Hammack in October 2014. Authorities believe they accidentally drove into the lake.