Brian Webb, 65, has been missing since Saturday evening. He was last seen on West Lakeshore Drive wearing a polo shirt, khaki shorts and a baseball cap.
On Monday, Vermont State Police Diving and Marine Units teamed up with Colchester Police and Technical Rescue to try to find him. They did find his dinghy on the east side of Marble Island. That also disappeared Saturday night.
"Well we've actually expanded the search area once. When we found the dingy in that location. We were hoping in finding the dingy that would narrow our search area, and it actually enlarged it," Colchester Police Lieutenant Douglas Allen said.
Colchester Police say the search will continue until dusk on Monday night.
They are using a side-scanning sonar from New York State Police to assist in the search.
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