Sydney - An Australian navy ship arrived at the coastal town of Mallacoota in Victoria on Thursday, which has been cut off since New Years Eve, to rescue thousands of people trapped by fires.
The ship, HMAS Choules, is carrying much needed food, water and medical supplies and could evacuate up to 1000 people at a time, a defence spokesman said.
Four thousand people have been stranded at the tiny town in the state of Victoria, some 500 kilometres east of Melbourne, since fleeing fires on Tuesday and seeking safety on the beach.
The town of around 1,000 residents is a popular holiday spot, which attracts thousands of visitors in summer.
Victoria's Country Fire Association Chief Officer Steve Warrington said it will be days, perhaps weeks, before fires die down and roads are cleared so people can drive out of Mallacoota.
"We have fire that is literally burning right across the road... we've noticed that trees have come down and blocking roads," Warrington told the national broadcaster ABC. "It is not safe to drive on those roads."
With food, fresh water and fuel running out in Mallacoota, Warrington said they will have to prioritize who stays and who is evacuated on the ship.
Earlier on Thursday, fire authorities in both Victoria and the state of New South Wales told tourists and all non-residents to get out of fire zones as an extreme heatwave is expected to hit and worsen bushfire threats over the weekend.
The Rural Fire Service declared a "tourist leave zone," stretching 240 kilometres south of the holiday resort town of Batemans Bay in New South Wales down to the Victorian border.
Deputy Commissioner Rob Rogers told reporters Thursday morning that the fire danger was far from over, and that conditions were expected to worsen on Saturday when another heatwave sends temperatures over 40 degrees Celsius.
Long lines of vehicles clogged the roads heading north and west from the evacuation zone Thursday morning. Many were unable to leave as petrol stations ran out of fuel or pumps didn't work due to power outages.
Police escorted petrol tankers Thursday morning to Batemans Bay, but towns further south were still unable to get enough fuel for all people to leave, New South Wales Transport Minister Andrew Constance told the ABC.
Food and water was also running low in many of the coastal communities which have been cut off from the highway since the fires hit Monday and Tuesday, the Rural Fire Service said.
The Bureau of Meteorology (BOM) said a heatwave with strong winds will roll over South Australia Thursday before reaching south-east Australia on Saturday.
Rogers said strong westerly winds coming with the heatwave are expected to cause the megafires in the Blue Mountains west of Sydney, the capital of New South Wales, to flare up and be blown towards communities on the edge of the city.
Meanwhile the smoke from the fires blanketed the nation's capital Canberra on Thursday with some people forced to wear masks even working inside buildings.
The BOM said the smoke level in Canberra currently makes it the most polluted major city in the world. On Wednesday, the air quality in Canberra was 20 times the level deemed hazardous.
Fires have raged across south-eastern Australia since October. More than 5.36 million hectares across the country has been scorched and more than 1,400 homes destroyed.
The national death toll has risen to at least 17 people, according to the Australian Associated Press, with dozens still missing.