To provide an anti-theft device which is a comparatively simple device and can easily prevent theft of and damages to warning devices.

A dam management apparatus 1 has a monitor station 10, and at the monitor station 10 monitors the state of a dam and transmits a warning in a specified case, and a warning station 20 which receives the warning from the monitor station 10 and issues a decree for warning to the peripheral area. The warning station 20 has at least a warning station receiver 22 which receives warnings from the monitor station 10, a warning station display/detection device 23 which detects the state of the warning station 20 and displays it, and a warning station transmitter 21 which transmits warnings from the warning station 20 to the monitor station 10. As the anti-theft warning device for dam management apparatus 1, the warning station 20 detects an abnormal state of the warning station 20 through the warning station display/detection device 23 and notifies the peripheral areas of the abnormarity, and the warning station transmitter 21 simultaneously transmits a warning that the warning station 20 is in the abnormal state, to the monitor station 10.

COPYRIGHT: (C)2007,JPO&INPIT