Brimbank Crime Investigation Unit detectives are investigating a suspicious grassfire at Taylors Lakes on Monday night.
Emergency services responded after a paddock at the rear of Rowell Place caught fire about 3.35pm.
Local police evacuated approximately 40 people from their homes due to safety concerns.
No one was injured during the incident however fences and sheds sustained damage.
Investigators have released CCTV of a man on a bicycle who they are attempting to identify in the hope he may be able to assist with their enquiries.
Anyone with any information is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au