Abstract: An alarm reporting system includes a control unit which services a supervised derived channel communicator, and a one-way radio communicator (preferably via the cellular telephone network), to provide for interactive operation of the derived channel unit and the radio transmitter according to alarm conditions which may arise at the premises, and the existing condition of the equipment comprising the system. The system is capable of communicating with a central monitoring facility, or mobile units (patrol vehicles or service vehicles) associated with the central monitoring facility, for enhanced security of the monitored premises.