A vacant home in Phoenix was badly damaged by fire early Wednesday morning.
Flames and smoke were flowing from the roof of the home in the area of 40th Street and Osborn Road when firefighters arrived about 4:20 a.m., said Phoenix Fire Capt. Tony Mure.
Firefighters were able to prevent the fire from spreading to a nearby home, but not before it caused extensive damage to the attic and roof of the house.
Mure said many roof trusses had collapsed and that an air-conditioning unit was beginning to fall through the roof.
He said the extent of the damage was evidence the fire had been burning for some time before firefighters were called.
The home has been for sale for several months, and neighbors told firefighters some men had been working on top of the roof on Tuesday.
Mure said investigators would try to determine whether the men on the roof were a work crew and whether maintenance was being done.
Though the roof was a complete loss, Mure said the interior of the home was "completely rebuildable."
The cause had not been determined and the investigation was continuing.
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