"The juvenile pulled up his shirt, he had a gun, he pulled the gun out, he racked it, racked the slide back, and basically challenged the security officer saying, 'Do you want some of this?'" said Fresno Police Lt. Joe Gomez.
The gun was later determined to be an airsoft pistol, which the teen removed pieces of to make it seem like a real gun. A witness told Fresno Police the teen jumped a fence and fled school grounds to the south.
Fresno Unified School District Superintendent Michael Hanson thanked that witness, along with Fresno Police and Hoover High staff for a textbook response to a scary situation.
"While it's frightening issue for our parents and a community, things like this do occur and we are in about a good a position as we can possibly be," Hanson said.
"I guess everyone's snapchatting it on the balcony of the new building about what's going on," said Hoover High junior Isaac Saldana.
It was the third day of the new school year, but before the day had ended, officers with Fresno police's gun crimes unit had found the teen in a neighborhood close to the school.
He was arrested for brandishing a replica firearm and violating his probation.
Hanson says Hoover High School will have even better lighting and security cameras in the near future. Like all Fresno Unified high schools, he says Hoover also has a Fresno Police officer on site.