A vast area of Australia’s east coast – including parts of the Sydney suburbs – is facing one of the nation’s worst-ever bushfire threats.

More than 85 fires are burning across the state of New South Wales (NSW), 46 of which are not contained.

Authorities had predicted “catastrophic” conditions for Tuesday, amid fears a southerly wind could cause the flames to change direction.

About six million people live in the region.

Crews are battling a front spanning 1,000km (620 miles) along the north coast of NSW, with several blazes “exceeding 100,000 hectares alone”, officials said.

On Sydney’s north shore, firefighting planes dropped flame retardant over trees and homes in the suburb of South Turramurra, as the bushfires came within 15km (nine miles) of the city centre.

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“Next thing I know the fire was opposite our house and it was massive and the police came and grabbed our kids and took them away,” resident Julia Gretton-Roberts told AFP news agency.

“My daughter is pretty freaked out.”

Authorities said the Turramurra fire had been brought under control, but one firefighter had suffered a broken arm and suspected fractured ribs.

Australia’s conservative government has refused to be drawn on whether climate change could have contributed to the fires, in a response that has drawn criticism.

“My only thoughts today are with those who have lost their lives and their families,” Prime Minister Scott Morrison said on Sunday.

People in vulnerable NSW communities have been urged to stay away from bushland, and to flee their homes before the fires escalate. More than 600 schools are closed across the state.

How bad are the fires?

Three people have died and more than 150 properties have been destroyed since the fire emergency intensified in NSW on Friday.

But authorities said they were now facing what could be “the most dangerous bushfire week this nation has ever seen”.

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Experts have compared Tuesday’s forecast to the 2009 Black Saturday bushfires in Victoria, when 173 people died.

It’s the first time that a “catastrophic” level fire warning has been in place across the greater Sydney area and in the regions to the city’s north and south. The highest level rating was brought in after the 2009 disaster.

EPA

What is a ‘catastrophic’ fire warning?

• .the highest point on Australia’s six-point fire danger scale

• .results from high temperatures, strong winds and dry ground

• .fires starting under these conditions will threaten lives

• .homes cannot be defended from catastrophic fires

• .the only survival advice is to leave at risk areas early

Source: Australian government

“Under catastrophic conditions, fires that start and take hold will grow and develop extremely quickly and become large fires very, very easily,” Commissioner Shane Fitzsimmons said.

What has happened so far?

At least 11 emergency warnings had been issued by 15:00 local time (04.00 GMT), warning people their lives were in imminent danger.

By mid-evening that number had been downgraded to nine, but the Bureau of Meteorology warned things might shortly worsen thanks to the southerly changes – powerful winds that could alter the path of some fires.

In a briefing at 20:00, Mr Fitzsimmons said up to a dozen homes were believed to have been damaged or destroyed on Tuesday.

He said firefighting efforts would be hampered overnight as water-bombing aircraft can’t be used in the dark.

“We’ve got a long way to go given the enormity of some of these fires. We’re relying very much on firefighters and people on the ground to deal with what the southerly change will bring.”

Mr Fitzsimmons earlier said 3,000 firefighters were on the front lines, boosted by crews from other states and New Zealand, as well as the Australian Defence Force.

Police are investigating reports that a fire in North Rothbury, in the Hunter Region of NSW, and at least two others, may have been started deliberately.

Fire authorities said a million hectares of land had been burned in NSW since the fire season began in September.

In the small town of Wauchope, 250 miles (400km) north of Sydney, resident Neil Coombes said his home was in the path of an oncoming blaze.

“My wife went home earlier and said, ‘is there anything you want me to get?’,” he told Reuters. “I said, ‘yes, I want you back here with me.’ If the house burns it burns, but I can’t replace her.”

What about other states?

To the north, Queensland has also declared a state of emergency as 55 bushfires rage in the state.

Though it was not facing such severe weather on Tuesday, officials warned conditions could deteriorate later in the week.

Fire crews in South Australia were tacking about a dozen blazes, while bushfires in Western Australia also sparked emergency warnings.

Is this linked to climate change?

Scientists and experts warn that Australia’s fire season has grown longer and more intense due to climate change.

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Officials have confirmed that 2018 and 2017 were Australia’s third and fourth-hottest years on record respectively, and last year the nation experienced its warmest summer on record.

The Bureau of Meteorology’s State of the Climate 2018 report said climate change had led to an increase in extreme heat events and raised the severity of other natural disasters, such as drought.

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Even if global temperatures are contained to a 2C rise above pre-industrial levels – a limit set out in the landmark Paris accord, agreed by 188 nations in 2015 – scientists believe the country is facing a dangerous new normal.

Last year, a UN report said Australia was falling short in efforts to cut its CO2 emissions.

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