Wildfires that grew out of control last week now stretch nearly 1,000 miles long in Australia's most populated state.
"We've got three major fires, one already in a built up area and two more that are potentially going to impact very heavily built up areas," said Rob Rogers, deputy commissioner of New South Wales' fire service.
"If our strategies don't work and weather materializes tomorrow that is forecast ... it could be absolutely devastating," Rogers told CNN.
A state of emergency was declared in New South Wales, as high temperatures and strong winds exacerbated the situation. More than 200 homes have already been destroyed.
Last month was also the hottest September ever recorded in the country, the non-profit think tank Climate Council said.
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