THE RURAL Fire Service Investigative Unit and local police have been investigating a number of suspicious fires around the Valley.
"Occasionally when we have an increase in the number of fires in an area we also have an increase in arson," said a spokesperson from the RFS.
"The two are often directly related."
One of the fires near Ramornie State Forest off the Old Glen Innes Road is being treated as suspicious.
The fire was tracked to a number of start points, some of which are suspected to have traces of combustible materials.
The fire is now burning over quite a large area, however no property damage has been re-corded.
"At this stage our enquiries are ongoing, however many of the fires that have occurred since August 16 are being treated as suspicious," said Rick Miller from the Rural Fire Service Investigations Unit.
Police are also involved in the investigation and are calling for anyone with information to contact Grafton Police on 6642 0222.