Students hold their hands in the air as they are evacuated by police from Marjorie Stoneman Douglas High School in Parkland, Fla., after a shooter opened fire on the campus. (Mike Stocker/South Fl …

Students hold their hands in the air as they are evacuated by police from Marjorie Stoneman Douglas High School in Parkland, Fla., after a shooter opened fire on the campus. (Mike Stocker/South Florida Sun-Sentinel via AP)