Abstract: Attempts to pilfer or tamper with condition detector structures such as smoke detectors, intrusion detectors or the like are discouraged by incorporating switch apparatus within the enclosure for the condition detector device. This switch is directly associated with the hardware required for attaching the housing to a wall, ceiling or other structure so that the normal condition alarm signal generated, such as, when smoke, intruders or other sensed conditions are present is simulated by the attempts at removal of the mounting hardware. The invention is particularly useful in conjunction with condition detecting devices having self-contained internal apparatus.