A man from Bangor accused of a causing a standoff with police has pleaded not guilty to a federal gun charge. 34-year-old Shawn Nobrega is charged with being a felon in possession of a firearm and ammunition. Police say he was the center of a 6 hour standoff last month on Main Street, near the Hampden town line. Several homes and businesses in the area were evacuated because police believed Nobrega had weapons. Police finally used tear gas to get Nobrega to surrender. He’s being held without bail in the Penobscot County Jail and is due back in federal court in January.