(AP) — The student who wounded two classmates and killed a teacher and then himself on a Nevada middle school campus was 12 years old.

Authorities say they’re withholding the Sparks Middle School student’s name out of respect for his family. But Washoe County School District Police Chief Mike Mieras released the seventh-grader’s age at a news conference Tuesday.

District police say the boy brought the weapon used in the Monday morning spree from home. They’re still working to determine how he obtained the 9mm semi-automatic Ruger handgun.

Police say the boy’s parents are cooperating with them and could face charges in the case.

Also at the new conference, police lauded the actions of 45-year-old math teacher and former Marine Michael Landsberry. They say he tried to stop the rampage before he was fatally shot in the chest.