New South Wales Prime Minister Barry O'Farrell said a 63-year-old man died of a heart attack while defending his home against bushfires in the Lake Munmorah area Thursday.
"We were hoping for a miracle but sadly it has now been confirmed there has been a fatality," O'Farrell said in a statement issued by his office Friday.
Thousands of people had been evacuated after more than 90 bushfires were fueled by strong winds and unseasonably high temperatures, the Australian Broadcasting Corp. reported.
Officials said they feared up to 200 homes may have been destroyed.
Michael Gallacher, police and emergency services minister, told the BBC "the speed and the ferocity" of the fires was something he hasn't seen for "many, many years."
Gallacher said he expected the "magnitude of the losses ... to be quite substantial."
O'Farrell praised emergency services agencies.
"Given the hostile conditions we saw yesterday, it's a testament to the professionalism of the members of the Rural Fire Service, Fire and Rescue NSW, National Parks and Wildlife Services, NSW Police and other emergency services agencies in NSW that we have not seen a greater loss of life," he said.
O'Farrell said he spoke with Australian Prime Minister Tony Abbott and was assured that "everything is being done" to get help to affected residents and communities.
Despite a drop in temperatures and winds Friday, more unseasonably hot weather is forecast next week.