In a security system for monitoring security in a predetermined space from outside the space, the security system comprising: (a) at least one detection means located in or near the space for determining a violation of security in the space, the detection means having a normal mode representative of no violation of security and an abnormal mode representative of a violation of security, (b) information storing means associated with the detection means for storing data indicative of either the normal or abnormal mode, (c) means associated with the information storing means adapted for receiving a first signal from a location outside the space and capable of transmitting a second signal to the source of the first signal the nature of the mode of the detection means stored in the storing means, and (d) a signal transmitting means for transmitting the first signal to the receiving means and for receiving therefrom the second signal indicative of the mode; the improvement wherein the signal transmitting means is affixed to a vehicle and is adapted to transmit the signal continuously at a predetermined distance from the space and to receive the indication of mode at a second predetermined distance from the space.