Firefighters are tackling a small fire at Denaby Crags in Doncaster.
Three separate areas of grassland are ablaze and one fire engine is dealing with the incident.
A South Yorkshire Fire and Rescue spokesman said: “One appliance is dealing with it.
“There are three separate fires and the firefighters are putting them out with beaters and a hose reel.”
The fire service received the 999 call at 6.40pm.