Analyse @MSNBC's tweets
NEW: 3 people, including shooter, have been transported to hospitals after a shooting at Great Mills High School, sheriff says
• All 3 injured are in critical condition
• shooter was 'engaged' by the resource officer
• Students are being evacuated out of the high school https://t.co/Nid3XDVyOu
• All 3 injured are in critical condition
• shooter was 'engaged' by the resource officer
• Students are being evacuated out of the high school https://t.co/Nid3XDVyOu