Potomac High School in Prince George’s County went on lockdown after a school resource officer notified police about a trespasser on school grounds.
During the investigation, the school officer learned the trespasser had met with a current student on school grounds. As he questioned the student, he found a gun.
The student was taken into custody and the school was put on lock down out of an abundance of caution, police say.
The former student was seen on camera leaving the school grounds.