The man who allegedly killed nine people Sunday morning in Dayton's Oregon District was once kicked out of Bellbrook High School for making a list of girls he wanted to kill, the Dayton Daily News learned in interviews with former classmates and school administrators.

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Connor Betts, 24, was shot and killed by Dayton police, ending a brief yet deadly rampage in which he allegedly killed his sister, eight others and injured 27.

Police said they haven’t yet established a motive for Sunday’s massacre. But acquaintances tell the Dayton Daily News the warning signs — signs of the shooter’s unusual obsession with killing and death — cropped up long ago.

“This isn’t a mystery to me,” said one middle school classmate. “I’m furious.”

The classmate, who spoke to the newspaper on condition of anonymity, said the shooter once said he fantasized about tying her up and slitting her throat. The fetish was so macabre that even the shooter admitted he was scared of his thoughts, the woman recalled him saying.

"He knew it wasn't normal," the woman said about the decade-old conversation. "He and I talked at length about him getting help."

The woman said she and her parents told Bellbrook police about the bizarre admission, but the woman said she felt she wasn’t taken seriously, despite the would-be shooter including her on a hit list.

Bellbrook police haven’t released information about any involvement they might have had with him.

Chris Baker, the former Bellbrook High School principal who resigned this summer, confirmed to the Dayton Daily News that the shooter was suspended for causing a lockdown by writing a hit list on a bathroom wall.

“I would not dispute that information, but I don’t want to get involved any more than just making that comment,” Baker said.

Sinclair Community College officials said the shooter enrolled there in 2017 and studied psychology, but he wasn’t taking classes this summer.

“We are actively working with law enforcement to provide any and all information we may have to assist them in the response to this horrific act,” said Steve Johnson, the college president.

Law enforcement executed a search warrant Sunday morning at a home in Bellbrook. A background check purchased by the Dayton Daily News listed the home as the shooter’s place of residence. Dayton police said the shooter’s adult criminal history was limited to traffic violations, such as speeding, failure to control his vehicle and failure to yield.

The newspaper also purchased a background check of the shooter’s social media history. Among the details that surfaced in the search were MySpace photographs of notebook sketches showing odd phrases handwritten in screamo music-style font. The posts appear to be about a decade old.

The sketches, confirmed by a friend of the shooter as authentic, featured nearly illegible writing with legible captions underneath, including “All Shall Be Annihilated,” “Bloodlust,” “Absolute Carnage,” and “Bloody Massacre.”

One of the shooter’s classmates, Demoy Howell, said he and the killer participated in Bellbrook’s Junior ROTC military program. Another said the shooter was one of the leads in Bellbrook’s production of “A Midsummer Night’s Dream.”

Howell never had a problem with the shooter, but remembers friends saying he made them feel threatened or uncomfortable. The rigor of the military program seemed to have a calming influence on the shooter, Howell said. After the lockdown, though “he kind of fell off the face of the earth.” The two later reunited while working at a fast food restaurant.

“He was always a bit of an oddball,” said Howell. “He had a dark sense of humor — jokes about people dying. He would wear all black. I remember sensing a dark energy around him.”

"I think this is less of a hate crime and more of an 'I hate everybody' crime," Howell said. "I honestly feel more comfortable now knowing that he's gone."