Kentucky State Police foiled a man’s plan to attack a high school after they received a tip from a New Jersey woman who said he had sent her a racist message on Facebook, authorities said.

Police traced the message to Dylan Jarrell, 21, of Lawrenceburg, Kentucky, and then discovered after searching his phone that he had been plotting to attack local schools.

Jarrell was arrested last Thursday and charged with two counts of second-degree terroristic threatening and one count of harassing communications after he sent Koeberle Bull, 40, unsolicited Facebook messages. An investigation showed Jarrell, who had a firearm and ammunition in his car, had threatened to cause a school shooting, and authorities deemed the threat “valid and imminent,” court documents said.

“There is no doubt in my mind that as a result of this investigation we saved lives,” Commissioner Rick Sanders of the Kentucky State Police said at a news conference Friday.

Two days earlier, Bull had logged on to Facebook from her home in New Jersey and found the messages from Jarrell.

“There is no such thing as white privileged,” said the message. “I hope your black children gets hung for you being so stupid,” he went on.

Bull’s three children are biracial and can be seen in her Facebook profile picture. Worried for their safety, Bull reached out to local authorities and contacted Kentucky State Police.

“I had no idea who this person was,” Bull told WKYT, a Kentucky CBS affiliate. “Something in the back of my head was like, ‘This isn’t right.’”

Jarrell was arrested a day later while backing out of his driveway, according to Sgt. Josh Lawson, a spokesman for Kentucky State Police. Authorities found a rifle, over 200 rounds of ammunition and a Kevlar vest in his car.

Jarrell admitted to authorities that he had sent Bull the message on Facebook, and that he had threatened a local school with a shooting, according to court records.

Jarrell had used his cellphone to search for instructions on how to successfully carry out a school shooting, Lawson said. The notes section of Jarrell’s phone “contained what could be described as a checklist that coincided with his internet search history,” he said.

“We often hear from the community, ‘Well, why should I call the police, because they aren’t going to do anything about it?’” Sanders said. “This is an example of how when you call the police, and we work closely together, we do something about it.”

Bull posted about the episode on Facebook after Jarrell was taken into custody. “The officer in this case was amazing quick,” she wrote. She did not respond to repeated requests for comment.

In the interview with WKYT, Bull said she was glad she had followed her instinct and reached out to authorities. “It can be an idle threat or it can be the next mass shooter that you’re stopping,” Bull said.

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