Detectives are hunting suspected arsonists after a huge blaze ripped through a Padiham recycling centre.
The massive fire engulfed the yard of the plastics processing plant in Park Road on Wednesday.
Police believe the fire was started deliberately by firebugs setting fire to large bails of plastic material in the compound around 3-30pm.
CCTV footage is being scoured by officers are appealing for information about how the fire was started and urged the people responsible to come forward.
DC Martin Legdon, of Burnley CID, said: “This was a reckless and extremely dangerous thing to do and it is fortunate that the fire was spotted and fire officers were able to extinguish it before it spread any further.
“If anyone has any information that they think could help us trace the people responsible then I would urge them to call us as soon as possible by calling 101 and quoting log number LC-20130724-1129.”
People with information can also contact the independent charity Crimestoppers anonymously on 0800 555 111 or on-line at Crimestoppers-uk.org.