MENOMONEE FALLS, Wis. — Police and the Milwaukee County Sheriff’s Office Bomb Squad responded to Messer Cutting Systems on Friday morning after an employee found a note threatening that a bomb was inside the building, Menomonee Falls police said. The evacuation began before 8 a.m. About 40 employees were not allowed to reenter while authorities worked at the site, according to police. The available update did not say whether investigators found an explosive or when workers could return. Fountain Boulevard was closed between Anthony Avenue and County Line Road during the response, but had reopened by the time of the update. Messer Cutting Systems makes equipment and solutions for metalworking, including oxyfuel, plasma and laser cutting systems. The police response temporarily displaced workers and disrupted access to the industrial site.