WINDER, Georgia — A 14-year-old student opened fire at a Georgia high school and killed four people on Wednesday, authorities said, sending students scrambling for shelter in their classrooms — and eventually to the football stadium — as officers swarmed the campus and parents raced to find out if their children were safe.

The dead were identified as two students and two teachers at Apalachee High School in Winder, about an hour's drive from Atlanta. Killed were two other 14-year-olds, Mason Schermerhorn and Christian Angulo, and instructors Richard Aspinwall and Christina Irimie, Georgia Bureau of Investigation Director Chris Hosey said in a nighttime news conference.