Firefighters from Sleaford have been among crews on the scene of a blaze involving a number of disused caravans at Honington.
Crews from Sleaford, Grantham and Brant Broughton attended the fire at a site on Lincoln Road just before midnight (Thursday/Friday).
According to a fire service spokesman, steady progress was being made by crews through the early hours.
After two hours, another crew from Grantham along with a water carrier from Holbeach remained on scene after the worst was extinguished using hose reels and a thermal imaging camera to detect hot spots.
It is believed to have been started by embers from a bonfire.