LOUISVILLE, Ky. (WHAS11) -- Marshall County officials said students did as trained in an active shooter situation when a 15-year-old open fired inside their high school this morning. Experts say simple planning and communication between administrators, teachers and students can save lives.

That planning is happening inside schools right here in Kentuckiana.

When the unimaginable happens, experts say the best thing a school can do is be prepared.

"Nobody really likes to talk about this but with some proper preparation you could cut down on the casualties and make things go a lot smoother," former Secret Service agent, Greg Gitschier said.

Gitschier considers himself an expert in this kind of planning. He has history doing threat assessments as a member of the Secret Service and now he's using that experience to discover vulnerabilities inside Kentuckiana schools.

"The problem is, all these schools are different- the school behind me has seven levels and the room numbers don't match up. So if this is the first time for a police officer, paramedic or EMT it’s very easy to get lost," he explained.

Gitschier said,” It’s important for a school to know the best way to get first responders in, and students out.”

He said that's a plan that should be shared with local police.

"With just a little bit of pre-planning you can take a lot of time off of a rescue event," Gitschier said.

He also suggests teachers learn how to secure their classrooms. Gitschier said, "If you're going to keep the children or students in the class, you want to somehow secure the door. Even if you have to put some desks up in front of it, turn the lights off, get in the corner away from the window."

That's a process he says should be practiced with students- he calls it an "intruder drill."

"If they hear shots fired, or they hear a PA or radio announcement, what are they going to do," he said.

Gitschier can be hired to help inside a school or business for active shooter preparation.

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