Federal agents continue to investigate the ex-con suspected in taking part in a string of bank robberies across Minnesota. Dubbed the “Man in Black” for dressing in black when he originally began committing the robberies, authorities say that 49-year-old Mark Wetsch has hit at least 6, and possibly 12 banks in the state. Wetsch was charged Thursday with holding up a bank in Brewster with a toy gun. He is also a suspect in a late December bank robbery in St. Peter, and the FBI continues investigating whether Wetsch is the serial bank robber. Wetsch was sent to prison in 2005 for defrauding a Twin Cities nursing home. After he was released from prison he teamed up with a former federal prosecutor to talk to groups about the consequences of committing crimes.