A Hudson Valley teenager helped police stop a teen who allegedly had plans to shoot up his school and kill as many students as possible.

On Wednesday, the same day as the tragedy at a Florida high school, the Fair Haven Police Department along with detectives from the Vermont State Police Department began investigating a school shooting threat at Fair Haven High School in Vermont.

A mother of a student who knew 18-year-old Jack Sawyer of Poultney, V.T., told police she learned Sawyer purchased a 12-gauge shotgun from Dick’s Sporting Goods and made threats towards the school, reports Seven Days Vermont.

Police interviewed Sawyer on Wednesday but found no evidence to make an arrest. According to NBC, Sawyer told police the gun was for target practice and he never made any threats towards the school.

On Thursday, the Dutchess County Sheriff's office contacted police in Vermont. A young woman from the Hudson Valley told the Dutchess County Sheriff's office that Sawyer sent her disturbing messages that threaten the Vermont high school.

"Just a few days ago I was plotting on shooting up my old high school so it's not like I really wanted a future anyways," one message read.

In another message, Sawyer wrote he supported the shooting in Florida.

"That's fantastic. 100% support it," he wrote, according to a police affidavit. He later added, school shootings were just "natural selection."

When authorities interviewed Sawyer a second time, he admitted that he wanted to shoot up the school and planned to buy an AR-15, reports NBC.

“This is a classic example of the person who came forward, from out of state, is the true hero out of this because they put aside everything else to say, ‘I think there’s a problem.’ And based on that, it allowed law enforcement to intervene and avert a potential disaster." Fair Haven Police Department Chief Bill Humphries said according to NBC.

According to Seven Days Vermont, Sawyer said he was inspired to kill people at a school after reading about the Columbine High School massacre. He also allegedly added he wanted to find ammo that would "cause greater casualties and injuries."

Police later found books on the Columbine High School tragedy, a gas mask, and journal labeled, "Journal of an Active Shooter." The journal included his plan and a kill list, reports NBC.

Sawyer's plan called to take out the school resource officer and then kill as many students as possible before killing himself, police say, according to NBC.

Sawyer was charged with attempted aggravated murder, attempted murder and attempted aggravated assault with a deadly weapon. He was sent to prison without bail.

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