Taking steps now to rehearse what to do in an emergency can help you react quickly when every second counts, the Federal Emergency Management Agency says.
Make sure you remember these three actions from FEMA to survive an active shooter incident:
Getting away from the shooter or shooters is the top priority. Leave your things behind and run away. If safe to do so, warn others nearby.
Call 911 when you are safe. Describe each shooter, their locations, and weapons.
If you can't get away safely, find a place to hide. Get out of the shooter's view and stay very quiet.
Silence your electronic devices and make sure they won't vibrate.
Lock and block doors, close blinds, and turn off the lights.
Don't hide in groups- spread out along walls or hide separately to make it more difficult for the shooter.
Try to communicate with police silently-like through text messages or by putting a sign in an exterior window.
Stay in place until law enforcement gives you the all clear.
Your last resort when you are in immediate danger is to defend yourself.
Commit to your actions and act aggressively to stop the shooter.
Ambushing the shooter together with makeshift weapons such as chairs, fire extinguishers, scissors, and books can distract and disarm the shooter.
For more tips on how to prepare and respond to an active shooter incident, click here.
Rick Coker with Top Gun Security also shared some tips about what to do in an active shooter situation.
"That isn't the time to be a hero," he said.
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Coker said that if you think through these scary scenarios ahead of time, you greatly increase your chance of survival. He spoke to ABC after a 2016 attack on the campus of The Ohio State University.
"You got three choices. You either run, hide or fight. Today's scenario, when you're outside and there are areas to run, that's the best thing. Escape. Get away. Move away from the threat."
"Sometimes you don't have a choice but to hide," added Top Gun Security founder and owner Jeff Moore. "But if they come to the room you're hiding in, you don't want to just roll over."
Moore said fighting is the last resort, and you don't stop until the threat is gone. Anything can be a weapon.
"Pretty much everybody carries a weapon with them all the time. It's a pen. It's a phenomenal weapon because once in the neck, break it off, we're done," said Coker.
As active shooter situations have increased over the last few years, so has Top Gun's business: from churches, private schools, and even hotels.
There are a few things they said you can install or keep around your own business to protect yourself in the event of an active shooter like panic buttons, surveillance cameras and a door bar.
They also said if you find yourself hiding in an active shooter/stabber situation, turn your phones off or on silent. And parents -- if this happens on your child's campus, wait for them to call you, because your phone call could give their position away.