Police had been knocking on doors of homes in the small rural communities of Baffle Creek, Deepwater, Oyster Creek and Rules Beach in Queensland state to advise residents to evacuate but some were refusing, Gladstone Region Mayor Matt Burnett said.
"When you have a police officer knock at your door saying a fire is coming, it is time to get out — it's serious," Burnett said. "There is no one in that area that is safe to stay," he added.
Hundreds of firefighters were preparing for worse conditions on Wednesday, when temperatures are expected to reach 40 degrees Celsius (104 degrees Fahrenheit) with winds reaching 40 kph (25 mph).
Large swathes of Queensland were experiencing record high November temperatures and the heat wave will continue for days, Bureau of Meteorology state manager Bruce Gunn said.
"This really has been an exceptional — and still is an exceptional — heat and fire event in Queensland," he said.
"We've seen all-time temperature records absolutely shattered — records that have stood for 60 or 70 years," he added.
Queensland Fire and Emergency Services Commissioner Katarina Carroll said the perimeter of the fire that began on Saturday had expanded to 66 kilometers (41 miles).