An emergency warning has been issued for an out of control bushfire burning in the outer Perth suburb of Upper Swan.
More than 100 firefighters are battling the 210 hectare fire, which is currently not directly threatening homes, Western Australia's Department of Fire and Emergency Services says.
"There certainly were properties under threat overnight in Copely Road but firefighters worked hard overnight to reduce the threat to those properties," a DFES spokesman told AAP on Monday morning.
A bushfire emergency warning remains current for people in an area bounded by the Great Northern Highway, Walyunga Road and the Swan River, and surrounding areas in the southern and eastern parts of Upper Swan.
"If the way is clear, leave now for a safer place," the warning states.
"Do not wait and see, leaving at the last minute is deadly."
An evacuation centre has been set up at the Altone Park Leisure Centre.
A watch and act alert has been issued for residents east of Upper Swan with the wind direction set to change to an east-northeasterly with blustery conditions expected.
"The fire is in a very inaccessible area up on rocky slopes heading towards Walyunga National Park," the DFES spokesman said.
Air support arrived at first light on Monday and is being used to protect firefighters battling the blaze.
DFES is being supported by Parks and Wildlife, SES ambulance and police.