PHOENIX -- Investigators are trying to figure out what sparked a fire at a vacant house in Phoenix.
A neighbor called 911 to report the fire shortly before 4:30 a.m. Wednesday. Firefighters arrived on the scene near 39th Street and Osborn Road to find flames shooting through the roof.
Firefighters got things under control quickly despite the danger of a roof collapse where the air conditioner was positioned. Crews kept the fast-moving flames jumping to neighboring homes.
The woman who lives next door said another neighbor pounded on her door to wake her up. She said her house was filled with smoke.
"I actually though somebody had a camp fire going," Lisa Ford said.
Ford also told 3TV's Tess Rafols that the home that burned has been on the market for quite some time. What's more, somebody was working on the roof all day Tuesday.
Investigators will try to determine if that work was a factor in the fire.
No injuries were reported.