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On July 24, 2009, Peter Achermann, 82, left his home in Staples to run a few errands, and vanished. He had been making plans to speak at his granddaughter's wedding the following day.

Cass County Sheriff Tom Burch sent out another call for information Monday. Achermann was last seen on Warner Road, by the Crow Wing River Bridge. The next day, searchers discovered his car stuck in the mud on a dead-end road a few miles northeast of Staples.

Despite searches and a $20,000 reward, no other trace of Achermann has been found. "We are diligent about bringing Dad home and our work is not yet finished," Achermann's son Franz said in a statement. Anyone with information is asked to contact the Cass County Sheriff's Office at 800-450-2677.