To automatically extinguish a fire by surely detecting the fire even in a closed environment like a garbage-housing room which is not viewed from an external part.

A closed heat-sensitive discharge head 24 to be opened and operated by receiving heat by a fire is arranged in the garbage-housing room 12 of a garbage truck 10. A container 20 filled with a fire extinguishing agent by pressurization is arranged in an external part and connected by piping to the heat-sensitive discharge head 24. When a fire occurs in the garbage-housing room 12, the heat-sensitive discharge head 24 receiving the heat by the fire is opened and operated, thereby to make the fire extinguishing agent be supplied from the container 20 and make the heat-sensitive discharge head 24 discharge the agent. Besides, an open discharge head 26 is arranged in the garbage-housing room 12, thereby to attain manual discharge by the switching operation of a three-way valve 22.