Authorities believe the cause of a fire that destroyed a Greenfields home was a charging lithium battery.
Firefighters were called to the Cherrytree Court property just after 11am on Sunday.
Two young boys passing by were the first to raise the alarm, alerting a neighbour who then called triple zero.
Koben Cook, 8, said it was difficult to watch his home burn.
"I saw the windows break, I saw the roof collapse," he told 9News.
"This is the first house fire I have seen and it was my house."
Mandurah Station Officer Paul Litterick said the fire quickly spread.
"When we arrived there was a lot of smoke, the garage was going well," he told 9News.
"We believe it started from batteries on charge."
It is understood the family have no contents insurance.
A GoFundMe page has been created to help the family financially.
The fire comes just days after the Department of Fire and Emergency Services warned of a rise in lithium-ion battery fires in WA.
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