A security system and method for detecting the presence of one or more persons in a location, by: directing a light source in the direction of the location; detecting reflections of the light source from the location by a light detector in order to form an image representing the one or more persons' eyes; and analyzing the image received on the light detector to identify and count the number of eyes on the image. Preferably, the analyzed information is then communicated to a remote facility for further processing. Appropriate action to take based on the analyzed information includes issuing an alert, turning on an alarm system, sending a message to one or more predetermined persons and/or machines.