A 42-year-old Pittsfield man was sent to prison after pleading guilty to a robbery charge.

Michael Bedford pleaded guilty to one count of armed robbery while masked in Berkshire Superior Court on Thursday according to the Berkshire County District Attorney's Office. Bedford held up the Greylock Federal Credit Union branch at 1644 North St. in Pittsfield back in December 2015.

Judge John Agostini ordered Bedford to serve a 7 to 8 year prison sentence at the Massachusetts Correctional Institution at Cedar Junction.

The investigation was done by members of the Pittsfield Police Department.