Prime Minister Scott Morrison announced on Saturday that Australia has called up 3,000 military reserves to fight the country's ongoing wildfire crisis, the biggest call-up in living memory.
The announcement was made the same day two people lost their lives to the fires.
Australia has been preparing mass evacuations over the weekend as it braces itself for one of the worst days thus far in the disaster.
"Today's decision puts more boots on the ground, puts more planes in the sky, puts more ships at sea," said Morrison, who has been heavily criticized for his response to the monthslong crisis.
Authorities confirmed that two people died due to wildfires on Kangaroo Island off the coast of South Australia, bringing the overall nationwide death toll to at least 23.
The island, popular with tourists and famous for its wildlife, also lost large parts of its Flinders Chase National Park to the blazes. Fires began on December 20 and have now burnt more than 1,000 square kilometres (386 square miles) of land.
"There will be very significant wildlife losses on the island," said South Australia premier Steven Marshall. The park is home to kangaroos, koalas and echidnas.
Local authorities say the fires are "virtually unstoppable" and will continue to burn for several more days.
Read more: Oceans play a role in Australian bushfires drama, say experts
Fires may reach Sydney suburbs
New South Wales Premier Gladys Berejiklian had called on residents in areas threatened by fires to leave as quickly as they can as the state braces for "another terrible day."
"All of the major road networks are still open but we can't guarantee that beyond the next few hours. So there are still windows for people to get out," she urged.
New South Wales Rural Fire Service Deputy Commissioner Rob Rogers warned that residents were "likely to lose homes" and that it would be "a success if no lives are lost."
"There is potential for the fire to break out, cross the (Warragamba) dam and move into the western suburbs of Sydney," he said. "That fire is burning. It has the potential to come out into more populated areas this afternoon,'' Rogers added.
"Leaving it until today is cutting it fine. The sooner you make that decision the better and I would say do it now. Don't leave it any longer because the window will shrink and will shrink very quickly."
More than 130 fires are burning in New South Wales and almost half of those are out of control.
Temperatures in parts of the state are predicted to soar in the mid-40s Celsius (113 Fahrenheit) due to low humidity and strong winds.
Victoria fires worsen
In the state of Victoria, a total of 48 fires were burning across almost 320,000 hectares (791,000 acres). Conditions are expected to worsen with a southerly wind change.
Local police reported heavy traffic flows on major roads as people evacuate.
On Saturday morning, the first of thousands of rescued residents and holiday-makers who were stranded on a beach in Mallacoota due to raging bushfires docked near Melbourne after a 20-hour journey by ship.
Around 4,000 people escaped to the waterfront on New Year'S Eve as fires ripped through the southeastern town.
"For someone who's never been in a fire, it's very, very, frightening. I'm so happy to be here," said 16-year-old Emily Wellington from Melbourne who had visited Mallacoota for a two-week holiday with family friends.
Australia's summer bushfire crisis has already destroyed about five million hectares (12.35 million acres) of land and damaged more than 1,400 homes.
mvb/kl (AP, AFP, dpa, Reuters)
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