Ex-Jacobs High School student taken into custody in lunchroom after showing weapon on social media

ALGONQUIN, Ill. (WLS) -- Five Algonquin police officers surrounded a 15-year-old former student at Jacobs High School, taking him into custody in the middle of the lunchroom on Monday.

It happened a short time after a student reported seeing video of the boy on social media, holding a gun on campus. ABC7 has blurred the face of a student not involved.

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The arrest came just as the school was going on lockdown. In a note, the superintendent informed parents of a concerning video on social media, in which the former student was seen displaying a weapon.

Police took the former student into custody without incident, conducted a thorough search, and confirmed he was not in possession of any weapons at that time.

School cyber security experts say prompt actions may have prevented a violent situation.

"Ninety-four percent of school shooters over the last 12 years posted online what they wanted to do before they did it," said Detective Rich Wistocki with Be Sure Consulting.

Wistocki retired after nearly three decades as an officer in Naperville, and he now devotes his time to training officers, school personnel and churches about how to prevent incidents of mass violence.

He says there are a number of common elements in mass shootings in recent years, including in the incidents at schools in Sandy Hook, Connecticut, Parkland, Florida, Uvalde, Texas and Nashville, Tennessee. The shooters all put out social media messages before.

"A common denominator in most school shooters is a fractured upbringing. They've been physically abused, sexually abused or mentally abused," Wistocki said.

One Jacobs High School parent worried about security told ABC7 he's concerned that a kid was able to get into the school when he was not supposed to be there. Authorities say the student who reported the social media post did the right thing.

"If you see something, say something and report something," Wistocki said.

Wistocki said so far this school year, students he has trained have helped prevent more than 50 school incidents that otherwise could have been tragic.