Department of Fire and Emergency Services Commissioner Wayne Gregson has confirmed the Waroona bushfire has devastated the Yarloop townsite.
Addressing the media at 8.30am on Friday morning, Commissioner Gregson said 95 homes were destroyed overnight by the fire which has now covered more than 50,000 hectares.
"Yarloop has been significantly impacted by this fire with 95 houses and a number of structures including historical buildings and workshops destroyed," he said.
"The fire has also torn through 70 per cent of the local school, the post office and our own fire station."
Three people are currently unaccounted for from Yarloop with a large number of the community evacuated to a local sporting field.
Attempts to move them to the Leschenault evacuation centre will be made at 10am on Friday.
Sixteen people have elected to stay and defend their homes in Yarloop which have been unaffected by fire.
Commissioner Gregson said huge wind gusts fanned the flames overnight with the blaze still out-of-control, unpredictable and moving quickly.
"We have had significant challenges throughout the night and there are slight injuries to three or four people," he said.
"I would like to thank the community for their patience and it is important they get a level of individual situational awareness.
"The fire is still unpredictable and people in the area need to be aware of their surrounds and the warnings we are putting out."
Emergency Services minister Joe Francis said the 200-odd firefighters still battling the blaze need to be commended for their efforts.
"To lose one-third of a townsite is going to be very challenging for that community and the state government will do everything humanly possible to help them recover from this," he said.
"A large number of the firefighters are volunteers and they have had a very tough night.
"We hope they will get some relief from mother nature soon."