Two crews from Preston were called to a bin fire that damaged a shop, say fire services.
The fire started at around 9am on 20 January in an alley to the rear of a convenience store on Lawrence Road in Penwortham.
A spokesperson for Lancashire Fire Services said: "The wheelie bin fire melted guttering on the shop and had the potential to be a very serious incident."
Cerw Manager Rob Barker added: "Deliberate ignition has not been ruled out at this stage. We would like to remind the public that deliberately starting a fire in these circumstances is a criminal offence. If the fire had spread to the building, the consequences could have been serious."
The cause of the fire is under investigation.
Nobody was injured during the incident.