A “mega blaze” raging across a 60km (37 mile) front north-west of Sydney cannot currently be put out, Australian fire officials have warned.

The fire across almost 300,000 hectares (1,150 sq miles) is an hour’s drive from the nation’s most-populous city.

People who cannot defend their property from approaching fires have been told they should leave immediately.

Since October, bushfires have killed six people and destroyed more than 700 homes across Australia.

The severity of the blazes so early in the fire season has caused alarm, and prompted calls for greater action to tackle climate change.

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Fires have also raged across Queensland, Victoria, South Australia, Western Australia and Tasmania.

Content retrieved from: https://www.bbc.com/news/world-australia-50690633.