Knoxville Schools Superintendent Dr. Randy Flack tells KNIA KRLS News that beginning Monday October 28, Knoxville School District will activate the entrance security system that was installed this fall. Doors in all buildings will be locked, except for the times when students are arriving and leaving school. Parents and visitors will be required to press a buzzer near the main entrance. A security monitor will allow the school secretary to establish identity, then buzz in the visitor. A visitor tag will be issued to the visitor, to be returned at the end of the visit.