CENTENNIAL, Colo. -

Students who were inside Arapahoe High School during Friday's shooting rushed to safety as soon as they heard gunshots.

One of those students, Hunter Rynders, got within just a few feet of the shooter. Hunter was in the library studying when he says he heard a loud bang.

After he heard it a second time Hunter says he knew the noise was gunshots. That's when he says the shooter busted in, screaming the name of the school librarian, Tracy Murphy. "He shoots one in the ceiling and he keeps saying where's Murphy, and he shoots another one into a box on top of the desk; I'm like 10 feet away from him," says Rynders.

Police believe the shooter, 18-year-old Karl Pierson, then took his own life.