Investigators said the shooter who shot and injured two students at Evergreen High School on Wednesday kept shooting and reloading, according to the Jefferson County Sheriff's Office, and that much of the credit for saving lives goes to the students and staff.

A boy opened fire with a handgun at a high school in the foothills of suburban Denver on Wednesday and shot two teenagers before shooting and injuring himself, authorities said.

Colorado Gov. Jared Polis, a Democrat and the nation’s first openly gay governor, called the attack “horrific, sickening and devastating.”