The danger from a bushfire in Perth's southern suburbs has been downgraded but authorities warn there is still a threat to lives and homes with conditions expected to change.
The Department of Fire and Emergency Services (DFES) downgraded the emergency warning for Medina, Calista and Leda in the City of Kwinana to a watch-and-act alert at 5.45pm (WST).
While it has been downgraded, DFES says people need to leave the area or prepare to "actively defend their homes" from a fire that has burnt through about 49 hectares.
The blaze is moving northwest and is out of control and dangerous.
"There is a possible threat to lives and homes as a fire is approaching the area and conditions are changing," DFES warns.
"Burning embers are likely to be blown around your home. Spot fires are starting up to 100 metres ahead of the fire."
People who have left the area should not return and those staying to protect their homes shouldn't rely on mains water as pressure may be affected.
"Close all doors and windows, and turn off evaporative air conditioners, but keep water running through the system if possible," DFES advises.
A watch-and-act alert has also been issued for people in Kwinana Beach, east of Rockingham Road and Patterson Road to the railway line in the City of Kwinana.
A bushfire advisory has been issued for people in Orelia, Kwinana Town Centre and Parmelia.
Aerial support has been sent to assist ground crews.
The cause of the fire is unknown.