WA bushfires threaten residents with 20m wall of flames, ember attacks

Flames up to 20m high and ember attacks are threatening residents in Western Australia, with authorities issuing an emergency warning.

The Department of Fire and Emergency Services said a fire in Manjimup sparked by a lightning strike was out of control.

Residents were warned that burning embers were blowing around homes and spot fires were starting up to 100m ahead of the fire.

The warning affected people in the vicinity of the Shannon National Park, 20km east south-east of Northcliffe.

"The fire started in the national park as a result of a lightning strike," the alert read.

"The alert level for this fire has been upgraded as the fire has broken containment lines.

"You are in danger and need to act immediately to survive. There is a threat to lives and homes."

Elsewhere, a fire in the Waroona township, south of Mandurah, remains out-of-control.

There are fears that with forecast strengthening winds, the fire will breach its containment lines.

The fire started south of Forrington Heights and is burning within the Waroona townsite. 

It has burnt 338 hectares since it started on January 29 and destroyed one home.

Yesterday, firefighters reported wind gusts of up to 100km/h, which were fanning the flames.

The gusts sent embers across homes, and started spot fires.

"The smoke was so thick you couldn't see a thing," said resident Tony Pisconeri.

Residents elsewhere in the Waroona shire are advised of smoke, road closures and dangerous driving conditions.