A parent reported that a Galaxy Middle School student in Deltona threatened to shoot up his school.

A 13-year-old boy from a Deltona middle school was arrested for threatening to shoot up his school, an incident that was not reported by school officials but by a parent, authorities said.

The incident occurred during a sixth period class at Galaxy Middle School and was reported to school officials and a school guardian but deputies only learned of it after a parent reported the incident, an arrest report shows.

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The parent reported the incident to the school via the Fortify Florida application, said Volusia County school district spokeswoman Kelly Schulz.

Officials are investigating to find out why school officials didn't call law enforcement or report the incident, Schulz said.

The parent called deputies around 5:42 p.m. on Monday to report that the 13-year-old had thrown stones at her 12-year-old when the child got off at a bus stop and broke a cell phone, the report said.

Responding deputies, who went to the child's home in Orange City, also learned that the 13-year-old boy had made a threat, saying, "I'm going to shoot up the school with my AK," a report states.

The teacher, William Jackson, who has a class of four children identified as emotionally behaviorally disabled, said the boy was lying on the floor behind a couch when he made the statement, a report states.

Jackson shared the information with the campus advisor, the assistant principal and a school guardian he believed was present at a teachers' table, investigators said.

Director of School Safety Richard Myers said law enforcement was not contacted at the time of the incident, the report details.

The Galaxy Middle School student was charged with threatening to discharge a destructive device, authorities said.

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