In 2016, numerous law enforcement agencies across the country have been attacked on the job.
It's the reason more agencies are reaching out to the Advanced Law Enforcement Rapid Response Training or the ALERRT Center at Texas State University.
In 2002, the Columbine High School massacre showed how law enforcement could no longer wait for SWAT teams to arrive on the scene to stop active shooters. Officers needed to get inside and immediately stop the threat.
But as we saw just a few months ago in Dallas, active shooter scenarios outside present a whole new set of challenges. This can mean different training for officers altogether.
That's where Exterior Response to Active Shooter Events or ERASE training comes into play.
KVUE got an exclusive look at one such training session in Leander in September. ALERRT instructors taught officers from different agencies across the state how to respond to active shooters outside, where the threat can come from anywhere.
"They can be elevated, they can be behind hard cover, behind concrete, behind vehicle blocks, behind tree lines where as inside its sheet rock, dry wall, things are pretty limited," said Coby Briehn, a lead instructor.
In June, Dallas police experienced this danger first hand when a gunman shot and killed five officers during a peaceful march. Several others were also shot. Not long after, Dallas Police called the ALERRT Center for more training.
Different scenarios show officers options on how to respond to threats. For instance, one outline trained officers how to go after a shooter who posed a threat to the public and had already attacked officers.
Instructors have been running these scenarios for more and more agencies across the country.
"It's just gaining momentum," said Briehn.
According to the FBI, active shooters killed more than 230 people in 2014 and 2015, nearly ensuring ERASE training continues.
"They realize, what happens if we go into a tree line, if we go into a park, if we go to a county to go assist a county agency or game warden?" said Briehn.
Another scenario included using a car to rescue and render aide to "down" officers.
It's training that gives officers more options in life and death situations because every second counts when you're trying to save a life.
(© 2016 KVUE)