MINNEAPOLIS (AP) - A Minnesota businessman -- and St. Cloud native -- convicted of engineering a $3.65 billion Ponzi scheme now lives in a two-person prison cell, awakened at 6 a.m. each day by clanging door locks.

Tom Petters, who led the Petters Group Worldwide corporate empire, tells Twin Cities Business magazine that he now teaches other inmates at the federal prison in in Leavenworth, Kan. how to develop business plans. He spends his evenings in the library, researching ways he might overturn his conviction and a 50-year sentence that could keep the 54-year-old in prison for the rest of his life.

In his first media interview since his arrest, Petters still maintains his innocence. He says he was betrayed by associates who took a legitimate business and turned it into a Ponzi scheme behind his back.

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