JACKSON COUNTY, Mich. (WLNS) — A 20-year-old Napoleon Community Schools student is facing a terrorism threat charge after he said he was going to shoot up the school’s graduation, officials say.

The Napoleon Township Police Department says they first learned about a series of threats against staff members and a resource officer with the district on May 31.

After an investigation, police determined student Nathan Mann of Napoleon posed a credible threat to the safety of school staff and officers of the department. When Mann’s home was searched, a shotgun, several knives, and a sword were found.

Mann was kicked out of Ackerson Lake School back in December for a domestic dispute with his girlfriend, police say. Mann was still set to graduate, but could not walk.

Police tell 6 News Mann left phone messages with the principal and school resource officer and threatened to shoot up the ceremony and stab an officer in the neck.

As he was being investigated for the threats, police say he started telling other students about his concerns of not being allowed to participate in the graduation ceremonies.

Those students reported to staff members that Mann had made specific threats towards teachers, staff members, and the school resource officer.

As the investigation continued, the school decided to issue a letter of trespass to Mann, barring him from being on the property of Napoleon Community Schools.

The Napoleon Township Police Department investigated the incident and interviewed several staff and students.

Ultimately, it was determined that Mann did in fact pose a credible threat to the safety of the school and the staff, police said.

Mann has since been charged and arraigned on two counts, one for false report or threat of terrorism, punishable by up to twenty years in prison, and one charge for intentional threat to commit an act of violence against a school, a school employees, or students with specific intent to carry out, punishable by up to ten years in prison.

Mann was taken into custody on June 3, and later that day, officers with the Napoleon Township Police Department executed a search warrant at Mann’s home.

During the search, they found the shotgun, knives, and a sword.

Mann was then arraigned in Jackson County’s 12th District Court and is being held at the Jackson County Jail on a $750,000 bond.

“The Napoleon Township Police Department would like to thank Napoleon Community Schools, the Napoleon Township Fire Department, Jackson County Office of the Sheriff, and the Jackson County Office of the Prosecutor for their assistance with each step of the investigation and the promptness and regard for which they gave each step of this investigation. Most importantly, we would extend a most sincere thank you to the students of Napoleon Community Schools. Without their willingness to get involved and their concern for the safety and wellbeing of their teachers and classmates, this investigation may not have been nearly as successful and certainly not at the speed at which it was.

Napoleon Township Police Department