FLEMING ISLAND – An 11-year-old student was arrested by the Clay County Sheriff’s Office after an investigation determined Trisden McMahon, a fifth-grader, sent text messages to another student on Aug. 30 indicating a desire to bring a handgun to Swimming Pen Elementary in his backpack to conduct a mass shooting.

According to CCSO, his texts were descriptive in his tactics and intent to go  classroom to classroom, shooting others, and then himself, if confronted by law enforcement to avoid being taken into custody. He also asked the other student to delete the chat where these statements were made. McMahon admitted to the threatening texts but stated he didn’t mean them. He further said he made the statements in anger over conflicts with other students.

Due to the detailed nature of his threats, where McMahon identified specific intent, named a weapon, and harbored a specific perceived grievance, CCSO conducted a full investigation. The investigation included searching McMahon’s backpack and room at home, interviewing all involved parties and family members, and seizing the suspect’s iPad for a forensic download.

As a result of this investigation, McMahon was arrested today on the charge below and transferred to the Department of Juvenile Justice — Duval Detention Center.

Florida State Statute 836.10: Written or electronic threats to kill, do bodily injury, or conduct a mass shooting or an act of terrorism makes it a second Degree Felony for any person to send, post, transmit, or procure the sending, posting, or transmission of, a writing or other record, including an electronic record, in any manner in which it may be viewed by another person, when in such writing or record the person makes a threat to (a) Kill or to do bodily harm to another person, or (b) Conduct a mass shooting or an act of terrorism.

"We take every single tip received very seriously and conduct a thorough investigation. I have zero tolerance for school threats,” Sheriff Michelle Cook said. “Parents, please speak with your children about the consequences of making such statements. I want to thank those who came forward with this information and encourage anyone who sees or hears anything suspicious to report it immediately."