EDMOND, Oklahoma - Edmond Public Schools (EPS) students are no longer in school, but employees had a professional development day.

Organizers said 685 of them chose to spend it preparing for what police said is not necessarily a new threat, but perhaps a more prevalent one.

The sound of gunfire rang out Tuesday in Cheyenne Middle School as hundreds of EPS employees went through intruder training.

Hoping to make this as life-like as possible without using live ammunition, Edmond Police Lt. Derick Pickard said his team set this up like a normal day at school; some doors open, some people in the halls and some in classrooms.

Teachers, administrators and support staff were put to the test and school resource officers with Edmond police were the role players and first responders.

“We would let the bad guy loose and let him go create his environment of terror and mayhem,” Pickard said.

Pickard said even though employees were surprised by the intensity of the exercise, their responses were impressive.

After each run through, police answered questions and helped the staff prepare for something they hope never happens.

Edmond Public Schools Chief Human Resources Officer Randy Decker said everyone working at the school is trained to make safety the highest priority.

“That’s a part of where we are in our world today, is that needs to come first before learning can take place,” he said.

The district hopes to put all teachers and staff through this training over the course of the next year or two.