The blaze at a house in the 300 block of Barneson Avenue was reported around 4 a.m. this morning, Chief Dan Belville said.
A mother and her four children safely evacuated the home, while two of the family's cats perished in the blaze, the chief said.
Fire investigators believe the fire started in detached lean-to structures behind the home and spread to the house, he said.
When firefighters arrived on the scene, smoke and flames had spread through much of the home and had damaged the side of a neighboring home, where residents also exited safely.
As of 7 a.m., fire crews remained on scene to mop up hot spots and sort through the rubble to salvage items from the home.
It is unclear whether smoke detectors in the home alerted the family to the fire. The cause of the blaze remains under investigation, Belville said.
The American Red Cross is also on the scene to help the displaced family find accommodations.