As informative as they are horrifying, these videos were produced to inform the public on how to survive an active shooter.

Los Angeles County Sheriff's Department

"If you do find yourself in the middle of a senseless attack, the 'why' doesn’t matter."

City of Houston

"It may feel like just another day at the office. But occasionally life feels more like an action movie than reality."

Texas State University

"If you ever have the misfortune to be in an active shooter event, you deserve to survive."

Auburn University, Alabama

"In the video, students use books, book bags, and other items that were readily accessible to throw once they had no other option -- only use this option as a last resort."

University of Arkansas Police Department

"Avoid, Deny, Defend."

San Antonio Police Department

"To be clear, this is not an anti-gun video."

Mount Pleasant Police Department, Texas

"Students made up to simulate injuries. Getting everyone in place. Then the unthinkable happens."

The Ohio State University Department of Public Safety

"The idea is to make it as hard as possible for the shooter to see you, find you or get to you."

Bergen County, New Jersey law enforcement

"Invader in school, lockdown procedures now in effect."