Crime scene investigators are focusing on a fire which destroyed a car and part of a carport at Goolwa South early on Thursday, May 10.
Police and fire crews received the emergency call at 2.30am, and when they arrived at the Colman Road house, they found a blue Mercedes hatch well alight under a carport.
The free-standing carport had also caught on fire, and MFS crews extinguished it, but not before it was extensively damaged.
An occupant of the property was taken to hospital as a precaution, but police reported no other injuries.
CSI attended and examined the site, but police are urging anyone who saw or heard suspicious activity in the area leading up to the incident to contact Crime Stoppers on 1800 333 000 or at www.crimestopperssa.com.au