SAN TAN VALLEY, AZ - Arizona public school students are training for more than fire drills now.
Local law enforcement is using realistic school shooting drills to prepare everyone from students to first responders for the unthinkable.
Pinal County deputies wanted the drill Wednesday to be a lesson students and teachers remember, so they know what to do if a gunman ever enters their school.
The drill began with first responders surrounding Poston Butte High School in San Tan Valley.
The scenario: several gunmen were inside and an unknown number of students had been shot.
"Crisis goes on in the school. Hundreds of kids are wandering in various directions, nobody knows what to do," said Sheriff Paul Babeu.
Victoria Vasquez was one of 150 students participating in the drill. As she hid in a classroom, she says she heard chaos all around her.
"It was terrifying, even though it was a drill. It was still terrifying," she said.
Gunshots echoed in the hallways and "victims" laid on the floor. Teachers like Tara Walter kept the students calm.
"We focused on our students, right there, making sure we got them out safely," Walter said.
From students and teachers to first responders and nearby hospitals, deputies say all of these people need to know what to do in case this nightmare ever happens.
"Thank God that it hasn't happened here, but we can either put our heads in the sand and say it will never happen here and maybe it won't, or we can prepare for the worst," Babeu said.
Many students like Victoria would rather learn what to do now than panic in the moment.
"This is real, this could actually happen, and all schools need to practice this," she said.
Officials say they're happy with everyone's response to the drill.