A blaze that forced families to flee their homes amid fears of an explosion was not started deliberately, police said.
An investigation was launched following the fire behind a garage on Blackpool Old Road, opposite Blackpool Sixth form College, on Sunday that left one man needing hospital treatment.
But detectives have since ruled out foul play and say there will be no criminal investigation.
The fire started in industrial units behind Barry and Wilkinson Tyres just before noon.
Emergency services set up an exclusion zone – meaning nobody was allowed within 100m of the incident – because of a number of “highly explosive” gas cylinders nearby.
But staff at the garage said they managed to avoid the worst of the damage, with the fire largely confined to the adjoining land.
One member of staff told The Gazette: “It was a bit of a shock. It is just one corner that’s affected – we are having to have the roof sorted. But we are open and trading.”
It was business as usual at the garage yesterday in spite of the work needed to repair the area affected by the fire.
Lancashire Fire and Rescue (LFRS) said the majority of the damage was at a demolition yard, where the blaze is thought to have started.
But a spokesman said it was hard to estimate the value of the damage at this stage.
LFRS said the cause of the blaze remains under investigation but police today confirmed they do not believe the fire was suspicious.
Det Sgt Simon Pritchard, of Blackpool CID, said: “There is no criminal investigation.
“We are satisfied, following a joint investigation with Lancashire Fire and Rescue, that it is not a criminal matter.”
Six fire engines were on the scene at the height of the blaze as firefighters used an aerial ladder platform to tackle the flames from above. According to initial reports, a number of vehicles parked on the land behind the garage were severely damaged in the fire.
Around 20 homes were evacuated on Sunday, with residents allowed to return by around 2.30pm.
A man was taken to hospital with minor injures and later discharged. Neighbours described hearings a series of bangs as the fire took hold, with one describing the situation as “scary”.