PHOENIX -- The mystery behind an early morning Phoenix house fire, where no one was home at the time, is solved.
The house caught fire after 6 a.m. Friday at 22nd Street and Greenway Road.
Firefighters say no one currently lives in the home. It is up for sale.
Investigators say a real-estate professional has been showing the home to potential buyers and it appears an exhaust fan in the ceiling was left on inside a bathroom during one of the recent visits.
With the fan constantly running, it caused a vent in the bathroom to overheat and spark.
Flames spread through the attic, causing significant damage to the roof.
Damage to the inside of the house is minimal.
Investigators say over-heated ceiling fan and bathroom vent are to blame for attic fire in house at 22nd St. and Greenway.— Jill Galus (@JillGalus) July 11, 2014