After learning that a gunman was firing shots and taking hostages on campus, a group of 4 police officers were first to arrive on the scene at Claremont High School. There was no time to wait for backup, they had to act quickly before more damage could be done and more casualties suffered.

With guns drawn, the officers formed a tight circle and made their way through a campus courtyard, flanked on both sides by apparently deserted classrooms. The gunman was nearby, the officers knew, although his exact location could not be pinpointed.

Suddenly, two students ran out of a classroom. With hands in the air they screamed, “He’s shooting at us! He’s shooting!” and the students made a beeline for the helping officers.

“Get down on the ground!” the officers yelled, but the frightened students kept running at them. A nervous officer panicked, and shot one of the students.

A moment later, the gunman emerged from another classroom and fired at the officers before retreating back into the room. He was trapped. Two officers moved in, while the other two kept guard at the room’s entrance. The gunman was finally subdued.

As the “Active Shooter” simulation ended, the officers, role players and observers gathered to discuss what just happened and reviewed the officers’ performances.

“I think our officers did really well,” said police Capt. Gary Jenkins. “The training went smoothly. The whole purpose of those exercises is not only to practice but to also learn from your mistakes so that they’re made here and not during the actual event.”

Despite the positive feedback, others found it somewhat disturbing that several role-playing students were mistakenly taken out during the multiple rounds of simulations, including police Lt. Jon Traber, who commented on the trigger-happy officers.

“We’ve instructed the role players to make it clear who they are supposed to be by keeping their hands visible and so on,” he said. “The simulation is set up to heighten the officers’ anxiety levels … but that shouldn’t be happening.”

Taking place on Tuesday and Thursday last week at CHS, the drill was part of a training program that Claremont PD has instituted ever since the Columbine High School shooting shocked the nation in 1999.

“Columbine changed the way law enforcement agencies approached these types of situations,” said Gary Sabol of Prepared Response, Inc., a Washington-based company specializing in software aimed at helping law enforcement agencies better manage emergencies at schools. “The response agencies are using is completely different.”

A “shooter” hides in the bushes at Claremont High School ready to strike at police during the Active Shooter training drill Thursday.

In conjunction with the gunman-simulation training, Claremont PD recently purchased Prepared Response, Inc.’s software, called Rapid Response, through a grant funded by the National Institute of Justice. Getting CHS on the system will make it the first school in southern California to utilize the software as part of the institute’s pilot program.

The software completely maps out the CHS campus, with photos, blueprints and emergency evacuation scenarios to help software users access the most detailed information of the school and its intricacies. Police officers and school officials can then access the information, even from patrol cars, in case an emergency arises.

“Nobody can really prevent a school shooting from happening,” Mr. Sabol said. “But with this, it just gives the Claremont police department another tool to help them respond that much faster, that much quicker and to get that much more critical information when and if this type of emergency occurs.”

The software is not only useful for major emergencies such as a crazed gunman or bomb threats, Mr. Sabol said. It can also be accessed for quickly locating gas and water lines in case of leaks or obtaining teachers’ contact information. In the state of Washington, all public high schools are required to use the software. It is also used throughout northern Californian and in 10 other US states.

After CHS’ information is made accessible to police officers in the coming month, Capt. Jenkins said he would like to see all Claremont schools connected to the system.

Although there haven’t been any major threats at Claremont schools thus far, Capt. Jenkins said several weapons have been confiscated from students in recent months, including knives, a handgun at San Antonio High School and a taser gun at El Roble Intermediate School.

“You just have to prepare for the worst and hope for the best,” he said. “And that’s what we’re doing.”