The man accused of robbing a downtown Waterville bank Monday was in court Wednesday.48-year-old William Adamchak of Waterville is charged with robbery, theft, and terrorizing after police say he robbed the Bank of America on Main St. in Waterville then left behind a backpack he said contained explosives inside the bank.On Monday Adamchak allegedly walked into the downtown Waterville bank, demanded cash from a teller, and claimed he had bomb.Another customer overheard this conversation and called 9-1-1.That customer followed Adamchak on foot to the Big Apple convenience store on Elm Street. After a short chase, police arrested Adamchak. The state police bomb squad was called in and Main street was closed off for a few hours. Authorities were able to determine that a backpack left in the bank by Adamchak did not contain a bomb.Adamchak is currently being held in the Kennebec County Jail on $500,000 bail. He due back in court in January.