SAN MATEO COUNTY, Calif. (KGO) -- Coincidentally, on the week of the mass shooting at the Gilroy Garlic Festival, the San Mateo County Office of Emergency Services has been hosting active shooter training sessions for Peninsula law enforcement agencies, fire departments, and other first responders.
In the scenario, there is one shooter and multiple casualties. The shooter's victims are mostly in the School cafeteria.
Law enforcement and firefighters respond quickly.
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They clear the classrooms, escorting students and teachers out while making sure the gunman is not hiding among the evacuees.
The injured are played by volunteers. The bloody makeup so realistic, the make-believe wounds on the body are hard to look at.
The dead are mannequins, and the rounds fired are blanks, but the scenarios are eerily realistic.
Officers and deputies are doing multiple things here.
They're protecting and helping firefighters and other first responders.
They're also asking people here where the shooter went and if he's alone.
"Nationally, the average is 98 percent chance it's only one shooter. However, we always prepare for the worst-case scenario," says San Mateo County Sheriffs Det. Rosemary Blankswade.
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San Mateo County fire Batt. Chief Bill Euchner says, "Each year, we'll make it a little bigger, a little better, and add more challenges that happen to us in real life."
In the scenario, the lone gunman runs through the cafeteria to a hallway.
Police chase him. Then they shoot him after he tries to get a shot at them.
They cuff the wounded man.
This week, 143 agencies on the Peninsula participated. So far, 143 officers have gone through the training.