Arizona State Forestry spokesman Mike Reichling said Friday this is the first time he has seen a train used at the scene of a wildfire.
Two Copper Basin Railway converted rail cars equipped with water cannons have been dousing hot spots near Kearny, about 85 miles southeast of Phoenix.
Railway President Jake Jacobson says each car can hold 15,000 gallons of water and disperse it as far as 250 feet.
The fire has torn through nearly 2 square miles of salt cedar trees since Wednesday.
Reichling says a handful of residents are not yet able to return to their homes.
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