Authorities say 49 homes and two sheds were destroyed by a bushfire in the Perth hills but four people unaccounted for have been found alive.

Four people feared victims of a bushfire that razed 49 homes in the Perth hills region have been found safe, while firefighters are still battling to control the blaze.

The one death attributed to the fire was that of a 62-year-old man in Hovea who collapsed on the roof of his house on Sunday while preparing for the disaster.

The fire, which tore through 650 hectares in the Shire of Mundaring on Sunday and also destroyed two sheds, was contained on Monday but firefighters were still battling to control it.

A watch and act alert remains for the eastern part of Parkerville, Stoneville and Mount Helena.

One resident tried to get back to their house on Monday afternoon and suffered burns to the hands and feet.

Noelene Michels, from Helena Valley, said she knew her house was close to the fire zone and that her son was still there, but she could not reach him due to roadblocks.

“We think it is ok, but we can’t get through to check,” she said.

Sally and Gary Elwood, from nearby Narla Way, already knew their home of 30 years was gone.

“I am a bit shocked, but until I physically see, it won’t hit me fully, but I have seen it on Facebook so I know it is ours,” Ms Elwood said.

“I know it is gone, but my glass is half full – the kids are fine, everyone is fine. We will just rebuild, at 48 – bloody hell.”

Mundaring Shire president Helen Dullard said many residents were relieved to escape the flames.

“Visually, it was a very ugly fire. It was scary,” she said.

People who lost their homes will be escorted to the ruins on Tuesday.

The fate of livestock and pets is unknown but residents are bracing for the worst, while some firefighters have been treated for heat exhaustion and bee stings.

Emergency Services Minister Joe Francis believes a power pole on private property caused the fire.

He said the blaze could have been much worse and wiped out hundreds more homes.

“We pray this is the last fire we see like this, but there are no guarantees,” he said.

“We deal with the lottery dealt out by Mother Nature.”

Mr Francis admitted he was frustrated that the fire preparation message was not getting through.

The WA government will donate $1 million to the Lord Mayor’s Distress Relief Fund to help victims.

It will also provide $3000 to those whose homes had been destroyed and $1000 for damaged houses.

Western Power says about 700 properties are without power – and will remain so for days – and more than 150 poles will need to be replaced.

“Poles and equipment are being delivered in preparation for the rebuild, which is not expected to be able to start before Wednesday,” a spokeswoman said.

Insurers have declared the fire a catastrophic event.

Attorney-General George Brandis said the Australian Government Disaster Recovery Payment would also be provided to eligible residents.

People can claim a payment of $1000 for each adult and $400 for each child.