A man claiming to have a gun held up about 15 people on State Street on Saturday night before being arrested by Madison police. Brandon Stull, 19, of Madison, was arrested for armed robbery at about 10:40 p.m. Saturday in the 700 block of State Street. Before his arrest, Stull allegedly terrified pedestrians by being very loud, boisterous and belligerent, claiming to have a gun while demanding money from the victims.