Firefighters said the house was "well involved in fire" by the time they arrived at 3:20 a.m. Sunday, The Arizona Republic said. Phoenix Fire Department spokesman Capt. Scott McDonald said there had been no electricity or water service to the home for several months, leading him to speculate the inhabitants had been squatting in the dwelling.
A fourth woman was able to escape and was being treated for minor burns and smoke inhalation.
"We've been seeing this around the Valley," McDonald said, "where people are in these homes (and) are basically living in them without power, without water – I don't know if they're foreclosed on or not – and then that leads to alternative methods of heating it, which leads to a lot of these fires we've been having."