A 13-year-old boy was arrested in Jacksonville, Florida, on Tuesday for allegedly bringing a loaded handgun with no serial number to school in his backpack, News 4 Jacksonville reported.

The boy was charged with possession of a firearm on school property and possession of a firearm with an altered serial number, after a school employee searched his bag and found a loaded .45-caliber semi-automatic firearm with the serial number filed off, per News 4 Jax.

A Jacksonville seventh grader faces criminal charges after a school official found a loaded .45 caliber gun and ski mask in his backpack. https://t.co/BVBeWkkaeB

— Florida Times-Union (@jaxdotcom) September 6, 2023

The West Side Elementary employee searched the boy’s bag because it violated policy that students could only have clear or transparent backpacks. In addition to the loaded gun, which contained seven rounds, the employee also found a black ski mask, reported News 4 Jax.

Duval School Police arrested the boy, but remanded him to the Department of Juvenile Justice, per News 4 Jax. (RELATED: ‘Get The Bud Light Treatment’: Firearm Safe Company Under Fire For Giving Customer’s Access Code To FBI)

The school will now increase security measures in the wake of the incident, News 4 Jax reported.

Though all Duval County High Schools have installed weapons detectors, only one middle school in the county has implemented them, according to News 4 Jax.

“It’s very scary. My son was nervous to go to school this morning,” Christal Adamic, whose son attends West Side, told News 4 Jax. “I think (the district) did good this time. They jumped on it, took care of it quickly,” Adamic concluded.