A spokesman for Lancashire Fire and Rescue said damage from the fire caused a suspect gas leak and residents affected were evacuated from their homes. People in the vicinity were advised to close their doors and windows.
Gas engineers were called out to attend the scene and the evacuated residents were allowed back in their home shortly after midnight.
The fire crews used two hose reels, four breathing apparatus, a triple extension ladder, the stinger appliance, and breaking-in tools to extinguish the fire.
Two casualties were assessed at the scene before one was taken to the hospital by paramedics.