Fire chiefs are treating the Padiham recycling centre inferno as “suspicious”.
Investigations have launched into the cause of the huge blaze which ripped through the Park Road plastics processing plant yesterday.
Police are now scouring CCTV footage after youths were spotted around the perimeter of the site in the run up to the fire which broke out at 3-30pm.
Group manager Mark Hutton,community protection manager for Pendle, said: “In this type of investigation we will always keep an open mind but there are lines of inquiry involving CCTV footage and youths seen leaving the scene around the time the fire was reported.”
He added: “We are treating the cause as suspicious.”