Winchester firefighters are still working to determine what started a second story fire at a home on Boone Avenue Tuesday.

The fire was reported at 4:11 p.m. Tuesday at 352 Boone Ave. Winchester Fire-EMS Battalion Chief Scotty Bell said the fire was in a second-floor bedroom.

“The resident heard a noise upstairs,” Bell said. “She went upstairs to check, opened the door and was overcome with smoke.”

The homeowner, Ellie Desauniers, and her granddaughter escaped the home without injury and called for help, he said.

Firefighters had the fire, which was contained to the bedroom, extinguished within about 15 minutes, Bell said. They spent another couple hours on scene checking for hot spots, he said.

As of Wednesday afternoon, the exact cause had not been established, but Bell said they do not believe it to be suspicious in nature.