A bushfire near Toodyay Road in Perth's hills has scorched approximately 650 hectares and is advancing westward, posing a significant risk to several communities.

Challenging weather conditions and the preservation of indigenous sacred sites are complicating firefighting efforts.

The origin of the blaze remains under investigation, with noted detrimental impacts on local ecosystems and infrastructure such as fences.

Authorities are deploying aerial firefighting tactics, including water bombers, and have closed roads to manage the situation.

An emergency warning has been declared for Red Hill, Millendon, Herne Hill, and Baskerville, with adjacent areas under a watch and act alert.

No residential property losses have been reported at this stage, as firefighters persist in their containment operations.

Local residents are urged to remain informed on the status of the fire by consulting the Emergency WA website for updates.