Arroyo High School in San Lorenzo was placed on lockdown Friday afternoon after a 15-year-old student was reportedly armed with a gun, Alameda County Sheriff's Office authorities said.
School resource officers located the student in class and detained the teen, Sgt. Ray Kelly said, adding a firearm was also located in the student's backpack. Officers from the California Highway Patrol and San Leandro Police Department also responded to the incident.
"They knew the student, right off as they walked in, and they went in and detained him without incident," said Alameda County Sheriff David Bonnell.
The firearm found was a loaded semi-automatic handgun. The student was arrested and transported to juvenile hall, according to the Sheriff's Office. Two additional students were detained as they are believed to be associates of the armed students, Kelly said.
This comes just a day before the March For Our Lives rally, where students and advocates will march for gun control safety in all classrooms.
"Honestly it’s just crazy that this happened just before the march," Arroyo High School student Deonte Irvin said. "All this stuff that’s going on in the world is not good. Stop the gun violence."
An investigation of the incident is ongoing.
