The fast-moving fire broke out just past 6:00 a.m. Tuesday inside a 2-story home on the 1400 block of N. Conestoga Street.
Heavy smoke was found throughout out the house when firefighters arrived.
The adjoining row houses were evacuated as a precaution. The fire department was checking for extension of the fire to other homes.
Officials say all residents are accounted for at this time and there are no reports of injuries.
There is no word on what sparked the fire.