Lincolnshire Police and Fire and Rescue are investigating the cause of a fire which ripped through an abattoir on Heath Road in Skegness.
Emergency services were called to the blaze at 7.50pm on Friday, February 24.
At the height of the fire, some 30 firefighters attended with five appliances.
Residents in the surrounding areas were advised to keep their windows and doors shut due to toxic smoke.
The incident was scaled down on Saturday morning.
A scene guard remains at the premises whilst a joint fire and police investigation is underway to determine the cause.
Police are appealing for any witnesses who saw suspicious activity in the area to contact Skegness CID by calling 101 and quoting incident number 409 of February 25.