To view the situation of a store by reproducing a required picture in a monitor center without increasing the costs of a device or dispatching any staff when an accident or trouble is generated in an unmanned store.

Video data DV from a television camera 11 provided at an unmanned store 1 are stored in a hard disk storage device 14 as monitor data DM corresponding to time data DT. When an emergency signal S2 or the like is generated in the unmanned store 1, the whole part or one part of the monitor data DM stored in the hard disk storage device 14 before and after the point of time of the generation are transmitted through a communication line 3 to a monitor center 4.