Firefighters were tackling bushfires that destroyed homes in the city of Perth amid a rare spring heatwave in Western Australia, with temperatures expected to reach as high as 40 degrees Celsius (104 degrees Fahrenheit) on Thursday.

Ten homes have already been destroyed, residents evacuated and several firefighters injured tackling the blaze in the city's northern suburbs, Western Australia deputy premier Rita Saffioti told a news conference.

"Today will be a difficult day for everybody involved, but again I want to thank all of those who have done so much to keep damage to a minimum," she said.

"It is important to note that their efforts have ensured that there has been no loss of human life."

Authorities said they planned to open a COVID quarantine centre that had gone unused during the pandemic to house those made homeless by the fires.

(Reporting by Alasdair Pal in Sydney; Editing by Sonali Paul)