Mesa High School said a student brought a loaded gun to school and threatened another student.
The incident happened on Friday but the school administration said it didn't know about it until Monday.
The school said the student brought the loaded gun to school. That student and another student then threatened a student.
Principal Kirk Thomas said a group of students were in the area when it happened but no students reported what happened.
"I am disappointed that these students compromised the safety of everyone at Mesa High School. This is not who we are. Thankfully a student did come forward and report the incident," Thomas said in a letter to parents.
The school didn't learn about it until Monday when officials found out the gun was on campus and a fourth student had it.
The gun was confiscated and the three students involved were arrested, Thomas said.
The full message to the parents can be read below.
Dear Mesa High parents,
This morning, we were made aware of a serious situation that occurred on campus last week.
On Friday, a student brought a loaded gun to school and threatened another student. A third student was also involved in threatening behavior with the gun. A limited number of students were in the proximity when this happened and no students reported it when it occurred.
School administration was not informed of these actions until this morning. We immediately contacted our school resource officer. During the investigation we learned that the gun was on campus, in the possession of a fourth student.
The gun was confiscated and the students involved were arrested.
I am disappointed that these students compromised the safety of everyone at Mesa High School. This is not who we are. Thankfully a student did come forward and report the incident.
It takes all of us to keep Mesa High safe. Please remind your child that weapons of any kind are not allowed at school, in parked cars or on the bus. Also encourage your child to speak up if they see or hear anything that may threaten the safety of our community.
Thank you for your continued support and for placing your trust in Mesa High School.
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