The report came during the lunch period on Friday afternoon at Tomball High School, TISD said. Officials said two campus administrators and two school resource officers apprehended the student and found the unloaded handgun inside a student's backpack, adding that there was no ammunition inside the gun.
TISD said the school employees' prompt response prevented the need to put the school in a lockdown, and that because the incident was contained within seconds, there was no active threat to students or staff.
District officials said appropriate disciplinary and legal procedures were underway.
"The safety and well-being of students and staff remain our highest priority," the district said in a statement. "We will continue to review safety procedures and reinforce expectations."