At least nine people, including two children, have died in bush fires in South Australia.
Some people jumped into the sea to escape the advancing flames
A combination of hot temperatures and strong winds sent flames tearing through many communities on the Eyre Peninsula, west of Adelaide.
Firefighters warned it could take days for outbreaks to be contained, although cooler conditions are now helping.
Police said seven people were missing amid the chaos sparked by the advance of the fires, and casualties may rise.
The flames have been fuelled by strong winds and summer temperatures that have reached 40C.
A BBC correspondent, Phil Mercer, says the ferocity of the fires has taken even the most hardened fire fighters by surprise.
Many residents in the Louth Bay area abandoned their homes and sought refuge on nearby beaches, police said.
Six people who jumped into the sea to escape the flames in the coastal hamlet of North Shields were picked up by a rescue boat.
All those who died appeared to have been trying to flee the fire in their cars.
Among them were a mother and two young children whose vehicle had apparently crashed in blinding smoke, police said.
Two firefighters were taken to hospital with serious burns, as the fire service struggled to contain the flames on Tuesday.
Water-bombing helicopters were brought in to help hundreds of volunteers on the ground.
The authorities say conditions are horrendous. More hot and windy weather is expected in the coming days.
Fire service spokesman Simon Vogel told Australia's Ten TV network: "There is no firefighting force in the world that can stop the fire in the conditions we experienced today."
Police inspector Malcolm Schluter said the fire had been "merciless" in its progress across the Eyre Peninsula. The number of properties destroyed is not yet known.
The cause of these wildfires remains unclear. Most are sparked by lightning strikes, arsonists or cigarettes carelessly thrown away by drivers.