Firefighters are investigating what caused a fire in Fleetwood at 5am.
Two fire engines were dispatched from Fleetwood at 5:18am, after reports of a fire on Whinfield Avenue.
Lancashire Fire and Rescue Service say that, at the scene, firefighters "discovered a fire involving a large quantity of sawdust and fencing."
Crews used two breathing apparatus and one hose reel to extinguish the fire, which caused heat damage to an adjacent outbuilding.
They spent two hours at the scene.
Lancashire Fire and Rescue Service initially suspected that the the fire was not started deliberately, but say that they are continuing to investigate what could have happened.