A Uniondale High School student was taken into police custody on Wednesday, accused of attempting to enter the building with a loaded weapon.
The student was caught with the weapon by the school's metal detectors, according to a letter on the district's website.
After the weapon was discovered, law enforcement was immediately notified and took the student into custody.
"Safety and security are paramount to our district," the letter reads. "This dedication is why we have measures such as metal detectors and a vigilant security team in place. Today's incident highlighted the importance of these measures. We commend our security team for its actions to keep our students and staff safe and secure."
The district did not identify the student.
Nassau police confirmed a 17-year-old had the loaded firearm.