In the U.S., fire departments respond to an estimated fourteen thousand high rise building fires every year. A test of drones being used as a means to fight fires in a high rise were conducted in Chongqing, China in January. Guofei General Aviation Equipment Manufacturing supplied the drones for the test in which they performed extremely well – putting out the 10 story blaze in about 15 minutes (perfect timing considering the 20 minute battery life of these drones). In the video, you see the drones slowly work their way down to the bottom of the building until the fire is extinguished.
However, further testing is still essential, because fire is very rarely only on the outside of the building. As any novice or seasoned firefighter will know, most fires have to be fought from within the structure.
This drone does stop one very specialized type of crime. Clothes line arsonists. That seems like the most likely time something would be burning 10 stories up on the outside of a building!