Stockton's Bear Creek High School served as a large training ground for law enforcement agencies from across San Joaquin County Wednesday afternoon.

It was a drill involving an active shooter on campus.

"The reason we did this is we want to be prepared in case there is something like this at a school, at movie theater or at a mall," said Stockton Police spokesman Joe Silva. "We want the community to know our first responders are prepared."

The drill was planned well in advance of the shootings in Tehama County.

In the practice scenario, there are multiple casualties.

This also gives first responders the chance to implement their Active Threat Plan, which relies upon a task force to quickly rescue and treat victims.

100 volunteer actors participated.

Half are simulated patients suffering from wounds to be treated by responders and hospital personnel.

Seasoned evaluators walk the scene checking out how responders are executing the active shooter plan.

33 agencies took part in the two hour drill.

It was the second year for San Joaquin County law enforcement agencies to participate in this type of drill.