Firefighters had to climb mounds of debris inside a house that caught fire early Thursday morning.
Debris in and around the house hampered firefighters' efforts to stop the flames at 3400 W. Missouri Ave., in Phoenix, Fire Capt. Tony Muir said.
Muir said the home was not occupied and appeared to be used as a storage unit, forcing firefighters to climb over furniture and other items "several feet deep."
He said firefighters had to break through outside windows and sliding doors to enter the house.
No cause had been determined.
No other information was immediately available.
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