A fire which threatened homes in Waroona last night has been contained and controlled.
Waroona residents were placed on high alert for the second time in as many weeks yesterday after a fire burned through more than 100ha in just five hours last night.
The Department of Fire and Emergency Services said there was still a possible threat to lives and homes due to wind changes expected later today.
There is no running fire, however small pockets of bushland are still burning and fire crews are mopping up at the scene.
More than 50 firefighters tackled the blaze, about 120km south of Perth, overnight after the advice level to residents was downgraded from an emergency to a watch and act.
Favourable conditions including easing winds which first pushed the blaze north-east and then north-north-west gave ground crews some respite as night fell.
A threat to lives and homes remained throughout the night as bushfire brigade, career, volunteer and Department of Parks and Wildlife firefighters worked to strengthen containment lines around the 123.5ha fireground.
Earlier in the day eight aircraft, including a Skycrane, dumped thousands of litres of water on to the fire.
For several hours the blaze was moving at 100m an hour, with burning embers flying ahead of the flames.
Huge plumes of thick black and grey smoke enveloped the area around Coronation Road as worried locals watched on.
One resident said an overgrown fire load along the Harvey River where the fire was burning had not been managed and should have been assessed and dealt with after a serious fire two weeks ago.
A suspicious blaze on February 23 burned through 200ha in a neighbouring area of Waroona, about 113km south of Perth, along Coronation and Buller roads.
It was in this area that yesterday's blaze started about 1.15pm.
The cause of the blaze is unknown.
Anyone with information about suspicious activity in the area should call Crime Stoppers on 1800 333 000.