Initial investigations suggest a fire was deliberately lit in Ulladulla on Tuesday morning.
About 8.15am on January 14, emergency services responded to reports of a grass fire on the western side of the Princes Highway at Ulladulla.
The fire was extinguished before it caused any damage to properties. No one was injured.
South Coast Police District officers established a crime scene, with specialist officers forensically examining the scene.
Residents reported seeing officers establishing a scene between Kings Point Drive and Pitman Avenue.
Initial investigations suggest the fire was deliberately lit, a police media spokesperson said.
An investigation has commenced under Strike Force Indarra, which was established earlier this month in response to bushfires on the state's South Coast.
The strike force is assisted by specialist investigators from the Arson Unit's Strike Force Tronto, State Crime Command, and across Southern Region.
As inquiries continue, strike force investigators would like to speak to a woman who may be able to assist with the investigation and are appealing for anyone with information or dashcam footage to come forward.
She is described as being of Caucasian appearance, 170cm tall, of a medium build, and with dark hair. The woman was last seen wearing a dark jumpsuit/overalls with bright colours on it.