TWENTY-SEVEN raging bushfires remain uncontained, one man is dead and hundreds of homes are feared destroyed across New South Wales in what has been described as the worst bushfire disaster in more than a decade.

A third emergency bushfire warning has been issued for a blaze in south-west Sydney near Camden Valley Way and Cow Pasture Road in Leppington.

And in a move which gave emergency services the jitters, a water-bombing helicopter became caught in power lines at Chain Valley Bay on the Central Coast this afternoon.

New fire Camden Valley Way and Cow Pasture Rd Leppington. Threat to properties. Emergency warning being issued. #nswfires — Rob Rogers (@robrfs) October 18, 2013

Report of large shed fully alight at Camden Valley Way fire. Crews in property protection at the moment. #nswfires — Rob Rogers (@robrfs) October 18, 2013

The NSW Rural Fire Services said this morning it will take weeks to tame the flames that have wreaked destruction across the state, forced the evacuation of thousands of people and destroyed hundreds of properties.

Police are investigating whether arson was responsible for all three of yesterday's fires which began yesterday in the Blue Mountains west of Sydney, news.com.au can confirm.

A spokesperson said officers were out in the field looking for evidence of arsonists lighting fires in yesterday's extreme climate conditions.

A 63-year-old man died in the NSW Central Coast yesterday after he collapsed while defending his Lake Munmorah home.

Two volunteer firefighters are being treated for injuries in hospital, NSW Premier Barry O'Farrell said, and two residents understood to be affected by fire are in intensive care at Concord Hospital.

Fire Services Commissioner Shane Fitzsimmons fought back tears describing the tireless work of his firefighters, many of whom have lost their own homes defending the lives of strangers.

"We have the best firefighters in the world. There's no doubt about it," he said.

Heartbreaking RT @seanrubinsztein: The Magennis family spent 10y building their dream home. This is what's left pic.twitter.com/hJjmBwvqzs — Julia Holman (@JulesHolman) October 18, 2013

But he added that he was concerned about how firefighters tend to beat themselves up after a disaster.

"The thing that always worries me is how firefighters always beat themselves up," he said. "You simply can't (save everyone)."

News_Image_File: Nakia Belmer looks over his mother's destroyed home in Sunny Ridge Road, Winmalee. Picture: The daily Telegraph

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- Biggest worries: Three emergency warnings have been issued this afternoon in Springwood (Blue Mountains), Rutleys Road (Central Coast) and Leppington (south-west Sydney).

86,000 hectares of country were burned yesterday and overnight.

- Plea - Don't be complacent: Despite cooler conditions and lighter winds across the state the situation remains dangerous.

Fire grounds are active and will flare up today, NSW Fire Services Commissioner Rob Rogers told ABC Local Radio in a plea for people not to be complacent.

- National emergency: Firefighters are on their way from the ACT, Victoria and even South Australia and Queensland to help battle the state's worst bushfires in a decade.

News_Module: NSW Fire Warnings

- Grave fears of more deaths: A crime scene has been declared at Yellow Rock in the Blue Mountains while the state coroner investigates whether any lives were lost in yesterday's inferno.

Emergency personnel last night told a number of residents that people were feared dead.

Houses are still on fire in the area, parts of the ground are still too hot to walk over and many red-eyed residents continue to wait anxiously to learn of the fate of their homes and pets.

"The ground is red hot, trees are falling down everywhere," said Kim Irwin.

@mcclellan_ben at Mount Victoria :"There's one house with the gas still burning,one where all that's left is the Australian flag." #nswfires — vikki campion (@vikkicampion) October 18, 2013

@mcclellan_ben at Mount Victoria :"There's one house with the gas still burning,one where all that's left is the Australian flag." #nswfires — vikki campion (@vikkicampion) October 18, 2013

A Blacktown police officer on scene said this morning: "It's still so dangerous down there.

"There are still fires everywhere and we don't know how many lives were lost."

Yellow Rock was yesterday surveyed by the state coroner but it is still unclear if investigators located any bodies.

- Downgraded: An emergency warning for the blaze which engulfed an area between Lithgow and Blipin was downgraded to a "watch and act".

The fire burning in the Central Coast areas of Doyalson North, Swansea, Carns Wharf, Murrays Beach, Cave Beach and Catherine Hill Bay is still considered an emergency.

- Icon burned: The iconic Big Prawn at the southern end of Lake Macquarie was also a victim of the fires just a month after a recent renovation.

The fire made its way onto the Pacific Highway and into a service station sheltering the prawn, and the dangerous concoction of fuel and fire engulfed the building.

The Pacific Highway from Swansea is closed, with police advising the public that anyone found driving through will face penalties.

News_Image_File: Channel 9 screengrab of burnt houses at Springwood after yesterday's devastating bushfire storm.

- On the move: A major fire at Lithgow, west of Sydney, is now heading in the direction of Bilpin and Mountain Lagoon in the Blue Mountains.

A number of properties were destroyed in this fire and an emergency warning remains in place for the district.

And a fire burning in the Central Coast areas of Doyalson North, Swansea, Carns Wharf, Murrays Beach, Cave Beach and Catherine Hill Bay is still considered an emergency situation.

The Rural Fire Service early this morning said homes were under threat on Government Rd, at Nords Wharf, but residents were told it was too late to leave and they should seek shelter. Residents have been advised to leave now if it is safe to do so.

"Only well prepared and actively defended homes can offer safety. If you plan to leave, or you are not prepared and there is a safer place nearby, leave now if it is safe to do so."

More than 1500 firefighters battled the blazes which started in hot and windy conditions yesterday afternoon.

A cool change early Thursday evening brought some relief to temperatures, but it also created new chaos, swinging fire fronts around and pushing blazes into new areas.

News_Image_File: RFS volunteers on Medowie Rd in the Newcastle area attempting to save homes last night. Picture: John Grainger

News_Module: Latest Fire Warning

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Commissioner Fitzsimmons couldn't confirm how many properties had been damaged, but said it was probably in the hundreds.

"We're not talking numbers in the dozens. The toll is going to be high."

So far 88,200.65 hectares of land have been burnt.

Numerous schools are closed today.

Originally published as Were NSW fires deliberately lit?