OXFORD TOWNSHIP, Mich. (NewsNation Now) — A Michigan sheriff said that a previous threat to a high school was not credible after at least four students were killed and another seven were injured after a 15-year-old student open fired at the school Tuesday.

Oakland County Sheriff Michael Bouchard said that the previous threat to Oxford High School in Oxford Township, a community of about 22,000 people roughly 30 miles north of Detroit, was investigated and deemed “non-credible” in an interview with NewsNation.

“There’s been a great deal of misinformation on social media, we actually investigated a possible threat earlier last month in that particular school district and deemed it to be not credible,” said Bouchard on “Morning in America” . “In fact, we ran it down and it came from an individual not only not in that school district, but not even in our state. And so there was a dismissal of that particular threat.”

School administrators posted two letters to parents on the school’s website earlier this month, saying they were responding to rumors of a threat against the school following a bizarre vandalism incident.

According to a Nov. 4 letter written by Principal Steve Wolf, someone threw a deer head into a courtyard from the school’s roof, painted several windows on the roof with red acrylic paint and used the same paint on the concrete near the school building.

Without specifically referencing that incident, a second post Nov. 12 assured: “There has been no threat to our building nor our students.”

“We are aware of the numerous rumors that have been circulating throughout our building this week. We understand that has created some concern for students and parents,” the administrators wrote. “Please know that we have reviewed every concern shared with us and investigated all information provided. Some rumors have evolved from an incident last week, while others do not appear to have any connection. Student interpretations of social media posts and false information have exacerbated the overall concern.”

Two Michigan sisters told “NewsNation Prime.” that there were threats about a shooting posted on social media for weeks before the mass shooting Tuesday.

“It kind of seemed inevitable that it was going to happen,” Haley Hull said on “NewsNation Prime.”

Both Bouchard and an undersheriff emphasized that Tuesday’s shooting was unrelated to the deer head or any earlier investigation by their office.

“We are trying to run down the rumor that some people knew about something, but may not have shared it,” Bouchard said Wednesday on “Morning in America”. “Certainly not with us. We know for a fact that wasn’t shared with us.”

Oakland County Undersheriff Mike McCabe said Tuesday evening he wasn’t aware of any prior threats.

“Please don’t believe everything you hear and see on social media,” McCabe said. “I’ve seen one screenshot of something about allegedly the shooter warning people not to come to school today but that was someone that got it from somebody.

A concerned parent, Robin Redding, said her son, Treshan Bryant, is a 12th-grader at the school but stayed home Tuesday. Redding said her son had heard threats that there could be a shooting.

“This couldn’t be just random,” she said.

Bouchard said Wednesday morning on “Morning in America” that investigators were still trying to determine a motive for the shooting.

“The suspect is not talking to us at the direction of his parents,” said Bouchard. “In Michigan, the law requires juvenile get parental approval before he talks to the police and they refused it and have hired an attorney. So we’re not getting direct information on motive from the suspect.”

The three students who were killed were 16-year-old Tate Myre, 14-year-old Hana St. Juliana and 17-year-old Madisyn Baldwin. Bouchard said Myre died in a patrol car as a deputy tried to get him to a hospital

“I’ve seen way too much death and way too many dead bodies over the course of my career,” Bouchard said. “But you know, what I saw in that school, when it involves children, that just, it’s so much harder on everybody, and it punches you in a way that, you know, will stay with you forever.”

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