SALEM – A Swampscott felon is facing a possible life sentence for allegedly robbing a Salem bank in September, after he was held on $100,000 cash bail following his arraignment Wednesday in Salem Superior Court.William C. Dumais, 58, of 18 Roy St., entered a plea of innocent to a charge of unarmed robbery before Judge Timothy Q. Feeley.Feeley agreed to continue the same bail amount as set earlier in district court, with the option that the defense may seek a bail review at another court date. In the meantime, Dumais remains held in lieu of bail at the Middleton Jail.Dumais, a Marblehead native with four children, is accused of holding up the TD Bank in Vinnin Square in Salem on Sept. 11 at 11:49 a.m.According to reports, the robber allegedly handed a note to the female clerk while demanding she put the money into an envelope. After receiving an undisclosed amount of cash, the robber fled on foot. No weapon was reportedly shown.Police arriving on the scene found Dumais hiding close by in a wooded area off Loring Hills Avenue.Dumais was on probation at the time for robbing a bank at the same location in 2004 as well as two other local banks. At that time, he was sentenced to serve 18 months to two and a half years in state prison and placed on five years probation at the time of his release.His next scheduled court date is Dec. 5 for a pretrial conference. Assistant District Attorney Christina P. Ronan is prosecuting the case and Thomas Pierce is his defense attorney.