Three children and a teacher killed in shooting at Bend, Oregon, elementary school

Police in Bend, Oregon, say a 16-year-old killed three children, ages 5, 8 and 11, and a teacher at Silver Rail Elementary School on Thursday afternoon. Police say an armed community member followed him into the school and shot him; he was dead when officers arrived within minutes. A 7-year-old and a 54-year-old teacher are in critical condition. Police have not given a motive, and the FBI is assisting.