VIDEO: Former owners of a historic vacant home that went up in flames near 13th and Monroe streets early Thursday morning said it was the target of an arsonist. According to the Phoenix Fire Department, when crews arrived, they declared it a defensive fire due to a large amount of fire in the house. Crews set up large streamlines to extinguish the fire while also extending hand lines to protect the surrounding homes. One home to the east of the original house fire did catch fire from the radiant heat.