SYDNEY – Bushfires in Australia's Victoria state burnt out of control on Saturday, with authorities issuing an evacuation order at the highest danger rating for hundreds of residents in the state's west.

The alert was for an area near the Grampians National Park, about 241km west of the state capital, Melbourne, and included rural towns such as Halls Gap, population 495.

"Leaving immediately is the safest option before conditions become too dangerous," Victoria's emergency services agency said on its website.

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One of the blazes, sparked on Tuesday by lightning strikes, spread overnight and had now burnt through more than 28,000 hectares, the agency said.

About 400 firefighters were fighting the fires, using more than 100 tankers and 25 aircraft, the Australian Broadcasting Corp reported.

"The fire has stablized since the wind has dropped," Country Fire Authority deputy chief officer Gary Cook told the broadcaster.

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Authorities have warned of a high-risk bushfire season this Australian summer after several quiet seasons compared with the 2019-2020 "Black Summer" fires that destroyed an area the size of Turkey and killed 33 people.