Gunman kills at least 17 people at Florida high school

A former student opened fire at a Florida high school Wednesday, killing at least 17 people and sending scores of students fleeing into the streets in the nation's deadliest school shooting since a gunman attacked an elementary school in Newtown, Connecticut.Frantic parents rushed to Marjory Stoneman Douglas High School to find SWAT team members and ambulances surrounding the campus as classes prepared to dismiss for the day. Live footage showed emergency workers who appeared to be treating the