Firefighters in Western Australia are battling relentless hot, dry and windy conditions as they struggle to bring a major blaze under control.
The fire is threatening regional communities north of Perth with an emergency warning in place for several residential developments including those at Ocean Farms Estate and nearby Seaview Park.
The Red Gully fire has already destroyed 9200 hectares in the shires of Gingin and Dandaragan.
There have been no reports of homes being lost, but pine plantations, olive groves and some sheds are believed to have been damaged.
About 200 firefighters are battling the blaze with strong aerial support, including two of the large air tankers flown in from Victoria.
Another eight major fires across WA were also being fanned by dangerous conditions with Fire and Emergency Services Commissioner Darren Klemm warning there was little respite in sight.
Mr Klemm said the extreme heat and forecast wind changes over the coming days were a catastrophic combination that could result in small fires quickly getting out of control.
"This week's weather conditions are some of the most challenging firefighting conditions I have seen in many years and unfortunately, weather conditions are not easing over the coming days, in fact they are only going to get worse," he said.
"These challenging conditions have been seen in Red Gully and surrounding areas where an out of control bushfire has been burning since Saturday and temperatures are expected to soar into the 40s from Thursday.
"We face the risk of new fires igniting and existing fires escalating, which would put extreme pressure on emergency services."
Emergency WA said conditions around the Red Gully fire were testing containment lines.
"Residents of Ocean Farms Estate and Seaview Park need to remain on high alert and enact their bushfire survival plan now," its warning said.
"If you plan to leave, leave now if safe to do so via Indian Ocean Drive in a southerly direction. Your life may be in danger if you stay."
Premier Mark McGowan called on everyone in the fire danger zones to remain vigilant.
"I urge all Western Australian to understand and acknowledge that this is a dangerous period," he said.
In other areas, a watch and act warning remains for a fire at Mundaring, east of Perth, with that blaze contained but not controlled, and bushfire advice messages are current for fires at Geraldton, north of Perth, and at Nowergup, north of the city.
Wednesday's continuing emergency followed an easing of the danger on Monday after a string of fires threatened various areas to the north and south of Perth, on the state's southwest coast and in the Goldfields.
With very hot weather forecast until at least Sunday, Department of Fire and Emergency Services Deputy Commissioner Craig Waters said the risk of more fires was high.
"Whenever you come into a period of really hot weather coupled with extremely high easterly winds, we're always going to be in for a world of hurt," he said.
