A criminal complaint was filed in the U.S. attorney's office for the Eastern District of Michigan, WDIV-TV, Detroit, reported, but the suspect's name is not being released pending his formal charging.
Agents said they began surveillance in early September at the Best Western Hotel in Allen Park, watching a man -- and at times two accomplices –- go back and forth between a Dollar General in Melvindale and hotel.
The men were seen purchasing baking sheets, oven cleaner and toothbrushes, all of them commonly used to bleach currency.
Agents said when they searched the room, they found "counterfeit $100 bills sticking out from underneath the mattress of the bed," counterfeiting supplies and a printer-copier.
The complaint said 49 counterfeit $100 bills and eight bleached $5 bills were found.
The man told agents he was using the counterfeit money to buy large amounts of marijuana, which he then sold.
He also had an outstanding federal warrant for violation of probation on a previous counterfeiting conviction, the complaint said.
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