By Natasha Brown

TURNERSVILLE, N.J. (CBS) — Washington Township police, fire and EMS converged on an elementary school Tuesday morning. The good news, nothing was wrong.

Cameras rolled as the school held an active shooter drill. About 20 first responders took part and 15 students helped make it look real.

First, there was quiet. Then, gunshots.

At Whitman Elementary School in Turnersville, the drill was set up to be as realistic as possible. The school was empty, save for first responders, school employees and actors — high school students playing victims.

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Some were injured, some were tagged as dead. Carol Ann Wesh watched as the scenario played out.

“I’m a nurse. I know that happens, but seeing the casualties on the floor, that people really do get hurt,” Wesh said.

This is the sixth drill held by Washington Township first responders this year. Senior Camryn Wade has been in some before.

“One of the ones I was at, we hid in classrooms,” Wade said. “They told you different ways to make sure that you’re staying safer during a drill.”

Students say the drills help them imagine the unthinkable.

“I wouldn’t be as calm as I was today, but I feel like I would have more of an understanding as to what to do,” junior Allisa Conti said.

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“They would know, ‘I’ve done this before. I know how to act. I know what’s going to happen. Police are going to come in and do their thing. They’re going to get us all out safe,'” freshman Jared Garofalo said.

Washington Township Police say it also holds active shooter drills in hospitals and health care facilities. They say they try to do as many as possible in a calendar year, and they hope they never have to use the skills they learn.