Werribee Fire Brigade is urging residents to report fires as soon as they see them, following a spate of grass fires along the river trail.
The brigade has attended six grass and scrub fires since Saturday morning, the most recent being yesterday (Monday) morning.
Four of the fires were beside the Federation Trail, in the area of Lock Avenue and Concord Crescent.
First Lieutenant Darryl Wells said both fires were treated as suspicious and police attended.
“Two fires were in the area of the CBD, at the rear of Hungry Jacks and Wyndham Park dam area,” he said.
“Both these fires were significant in their area of spread and the heat present, and also treated as suspicious.
“The fires threaten not only the people using the walking tracks, but the beauty of the river valley, the habitat of the ground-dwelling wildlife. If they gain sufficient intensity, they could threaten property that backs onto the river.”
Mr Wells said ground fuel in these areas was burning with intensity and spreading rapidly.
Anybody witnessing any suspicious activity is urged to contact Crime Stoppers on 1800 333 000.