Crews from across Nottinghamshire and Derbyshire are continuing to deal with a large outdoor fire at Strawberry Hill Heath in Rainworth.
Firefighters from Ashfield Fire Station were among those called to the scene last night.
Nottinghamshire Fire and Rescue Service said crews were still working to extinguish the fire, which may appear to be producing only smoke but is still burning underground.
Specialist equipment from wildfire units is being used at the scene.
The fire service has asked people to avoid the area while firefighters continue their work.
A spokesperson said fires of this type can be difficult to put out because they can burn deep underground.
The service has also urged people to take extra care outdoors at this time of year, particularly with barbecues, cigarettes and glass bottles, and to take rubbish home after visiting open spaces.
