Just two days after the largest school-shooting in Parkland, Florida, plans for another, unrelated, violent attack on El Camino High School in South Whittier, California, was being hatched.

Thankfully, the school's security officer, Marino Chavez, swiftly responded by contacting authorities after overhearing a discussion of a planned mass shooting.

Deputies from the Norwalk Sheriff's Station were alarmed after receiving the call about a planned attack on the school that was to take place in three weeks. They began an immediate investigation on the 17-year-old male suspect who allegedly said, "I guarantee you the school will be shot up in three weeks."

According to the Los Angeles County Sheriff's Department Facebook page, the station detectives served a search warrant at the suspect's Norwalk county residence.

The suspect, whose name wasn't released due to being a minor, had a history of discipline at the school and had a Smith and Wesson semiautomatic rifle registered to his address.

He was detained for making Criminal Threats after detectives found "a cache of ordnance, including two AR-15 semiautomatic rifles, two pistols, 90 high-capacity magazines, and ammunition, and placed them into evidence."

The subject's 28-year-old brother, Daniel Eriberto Barcenas, an army veteran, claimed the firearms were registered to him, but one of the AR-15 semiautomatic rifles was found to be unregistered according to the sheriff's report.

The Sheriff's department isn't taking any chances, especially in the aftermath of the Parkland High School shooting.

The issue of violent threats on school campuses is something our agency takes very seriously. In 2017, our Criminal Intelligence Bureau received 52 tips or leads involving school-related threats, all which were triaged, evaluated and assessed. Seventeen of the threats involved community college students who were thoroughly evaluated and monitored by a collaborative effort between our Community Colleges Bureau and Criminal Intelligence Bureau personnel, and Los Angeles County Department of Mental Health and Federal Bureau of Investigation personnel.

Chavez, a 26-year-veteran as officer on the campus who overheard the threat, recalled approaching the teenager after hearing his plot, but the student laughed it off, saying, "He didn't appear scared, but he was like, 'Well, I didn't mean it.' I said, 'I know you students say a lot of things. But you can't be saying these words.' "

Barcenas was arrested on February 20, "for the charges of Possession of an Assault Weapon, Thumbhole Stock, Import of High Capacity Magazine, Possession of High Capacity Magazine, Criminal Storage of Firearm, and Failure to Register a Personal Handgun."

On Thursday, Barcenas pleaded not guilty to the illegal firearm charge.

A child making such threats, whether intended as a joke or not, is something that should be taken seriously. Sheriff McDonnell said, "The idea of committing such acts is staggering and increasing nationwide."

He implored parents to have a discussion with their children to address the current state of affairs.

Parents, this should be a wake-up call for all of us. Please, talk to your kids, no matter how young, about the challenges we are facing in society today. If you don't, someone else will.

The Sheriff thanked Chavez for taking action and called him an "unsung hero."

"I'm not a hero," said Chavez. "I'm just doing my job every day."

H/T - People, Facebook, Twitter, KTLA