Systems and methods for notifying law enforcement officers of armed intruder situations

A computer-implemented method executed by one or more computer servers includes receiving a notification from a first communication device. The notification indicates an armed intruder within a first stationary geofence. The method further includes determining whether one or more of a first plurality of communication devices are within a second stationary geofence different than the first stationary geofence, and in response to the notification, providing an emergency alert to the communication device(s) determined to be within the second stationary geofence. Other example computer-implemented methods, communication devices including software applications, and systems for notifying one or more LEOs of an armed intruder by a premises personnel associated with a premises are also disclosed.