As the country reels from the mass shooting in Thousand Oaks, California, experts are re-evaluating how they teach active-shooter training.

Twelve people were killed in the crowded bar during a country western music night in California, including Ventura Sgt. Ron Helus, who was killed as he rushed in to help. The gunman, Ian David Long, apparently took his own life.

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Maj. Jake King with the Marietta Police Department said the old adage of “run, hide, fight” is no longer the rule of thumb to escape an active shooter situation.

“The first thing we are teaching is to avoid. We want you to get out of the area,” King said. “If that includes breaking out windows, going through ceiling tiles … you name it – whatever you do, get out of the building, if that’s an option.”

The next thing, King said, is to keep the shooter from moving around a building.

“Anywhere from locking the door - if it’s lockable - to barricading the door and putting things in front of it to slow them down, to a door that has a hook – put a rope or purse around it and lean away from the door to keep it closed,” King said.

Lastly – as frightening as it sounds, King said it’s important to defend.

“The numbers are on your side – it’s usually one versus however many,” King said. “However, many people are still going to get injured. But hiding under the table is not the answer. Actively being involved and defending yourself is.”

Another thing to consider is that, in some cases, the shooter might pull a fire alarm to create chaos and panic.

“Of course, if you smell smoke, yes it’s time to go,” King said. “If not, just take a moment to evaluate why the fire alarm was pulled.”

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King also made one thing clear: don’t hide.

"Hiding and hoping is not the answer. Instinctively, as children, when we did tornado drills, earthquake drills, depending on what part of the country you're from, we were told to get under desks or hide under things when something traumatic or life threatening was happening,” King said. “We do not want you to do that.”

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