A derelict building at a caravan site in Poulton was set on fire in a suspected arson attack, say fire services.
Two crews from Blackpool were called out to Poulton Plaiz caravan park on Garstang Road at around 9pm on July 24 after occupants of the caravans spotted smoke.
Crews battled the blaze for around 30 mins using hose reels and ventilation fans.
A spokesman for the fire service said: "We were called to a fire in some derelict farm buildings at a caravan site in Poulton.
"Two pumps were sent and they tackled the fire using hose reels and ventilation fans.
"Not much damage was done as the building was already derelict.
"These incidents are a concern though, as we go into holiday season.
"The building was boarded up downstairs and the people who set this fire could easily have gotten into difficulties.
"They could have become overcome by smoke and they might not have been able to escape the property. "
Crews were at the scene for around three hours investigating the incident.
Nobody was injured during the incident.
A police investigation has been launched.