A suburban Chicago high school was placed on lockdown after a 16-year-old student was spotted in a bathroom with a gun and ammunition.

The unidentified Barrington High School student was arrested Monday on allegations of bringing a gun to school. Authorities say no shots were fired and no one was injured in the incident.

Assistant superintendent Jeff Arnett says an employee saw the handgun when it fell out of the boy's backpack. The student was quickly apprehended, questioned to ensure there were no accomplices, and taken to the Lake County Jail.

Barrington police Chief David Dorn and District Superintendent says students and staff were safely secured in their respective rooms for about an hour.

District officials say there will be an increased police presence on the high school campus for "the foreseeable future."