Three people are dead, five are unaccounted for and more than 150 homes have been destroyed as New South Wales's unprecedented bushfire emergency continues through a second day.

One fire remains at emergency warning level in NSW — at the height of the chaos on Friday, 17 blazes were given that status.

Firefighters said they found one body in a vehicle near Kangawalla, about 10 kilometres east of Glen Innes, where one of the most intense blazes took hold in the state's north.

The Rural Fire Service (RFS) confirmed on Saturday morning another person, a woman, died in hospital after she was found by authorities with severe burns near Glen Innes.

"The reports were initially burns to 40 to 50 per cent of her body," RFS Commissioner Shane Fitzsimmons said.

The woman has been confirmed as Vivian Chaplain, 69, who died while protecting her home at Wytaliba, north west of Coffs Harbour.

Elsewhere, NSW Police said a body was found in a burnt-out building at Johns River, north of Taree on Saturday afternoon on the state's mid-north coast.

A fire bombing helicopter works to contain a bushfire in Old Bar, NSW. ( AAP: Shane Chalker )

The other people still unaccounted for are in the Glen Innes area, and Mr Fitzsimmons said the number was expected to increase.

"That is not necessarily a [reason] for alarm, but we cannot rule out that the really great concerns that there could be [more] fatalities," he said.

Prime Minister Scott Morrison said the Australian Defence Force would provide support to firefighters where required and financial assistance would be made available to people affected by the fires.

NSW Rural Fire Service personnel conduct property protection in Woodford, NSW. ( AAP: Dan Himbrechts )

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 2 minutes 19 seconds 2 m 19 s Firefighters film the moment they drove through a ferocious blaze last night

Authorities told the ABC 60 structures had been destroyed in the Glen Innes area, including homes, sheds and some buildings at the public school.

The town's mayor Carol Sparks described the situation as "horrific".

"The school was lost, [houses] were burnt, people were burnt, lives were lost," she said.

"People battled to save their houses and then had to walk out because their cars had blown up, it was just horrific."

A bushfire came close to properties in Woodford, a village in the Blue Mountains in NSW. ( Facebook: Donna Mulhearn )

What is left of the residence at Four Paws Boarding Kennel near Taree. ( AAP: Darren Pateman )

The Insurance Council of Australia has declared the NSW north coast bushfires as a catastrophe, meaning those affected will be prioritised by insurers with many policies including emergency accommodation.

In Nymboida, where the Liberation Trail fire has burnt through more than 49,000 hectares, residents spoke of their devastation.

Peter Simpson told ABC News said he had saved his home and was thankful to be safe.

"It was like an inferno, like the apocalypse," he said.

"Every second house is gone … The village is gone. And surrounding houses, that I guarantee, most of Nymboida will be displaced because they're going to have nowhere to live.

"I'm really sorry for every person in the area that's lost out … My heart bleeds for them. There's nothing that the firies could have done."

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 3 minutes 3 seconds 3 m 3 s Nymboida residents survey the damage

As of 4:30pm Saturday, there were 81 fires burning across the state, with 36 uncontained.

Mr Fitzsimmons said a number of firefighters had been injured in battling the blazes, but none of the injuries were life-threatening.

"They have ranged from smoke inhalation to minor burns, to other injuries associated with slips and falls, through to serious lacerations to an arm," he said.

There are about 1,000 firefighters on the ground with 300 support staff.

At Wallabi Point, 90 kilometres south-west of Port Macquarie, residents were spotted on Saturday morning sheltering from the Hillville fire, the remaining blaze at emergency level.

Watch Duration: 26 seconds 26 s Watch Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Evacuees sheltering on the beach at Wallabi Point

Speaking on Saturday morning, NSW Premier Gladys Berejiklian said the situation was "beyond serious".

"These [are] fires that we have not seen before," she said.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 9 seconds 1 m 9 s Aerial vision shows houses on fire in Hillville

Homes were destroyed by a blaze at Hillville, south-west of Taree, which also ripped along the Pacific Highway and burnt trucks.

In Bobin, 85km south-west of Port Macquarie, several homes were destroyed and the school, which dates to 1883, was razed.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 48 seconds 48 s 136-year-old school at Bobin razed in NSW fires (Photo - ABC News: Lily Mayers)

A satellite images shows the devastating bushfires across New South Wales. ( NASA Earthdata )

Speaking from his home, which was caught up in the Hillville fire, Mid Coast Council Mayor David West said he feared for people living in the area.

"It is a monster," he said.

"It is such a tinder-dry environment, [and] the amount of water that we have available is critical at the moment.

"I plead with people that aren't affected by the fires to ration what water they're using, because it may get to the point where we need the water we have available, potable water, to fight the fires.

"It is that bad."

In a Facebook post, the RFS said: "While conditions have eased compared to yesterday, Very High fire danger will continue for many areas today."

Port Macquarie appeared apocalyptic on Friday as the sky turned red and thick dark smoke engulfed the regional centre.

Lighthouse Beach at Port Macquarie was barely recognisable on Friday. ( Supplied: Laura Begbie )

Yesterday, there were multiple reports of people being trapped in their homes.

Some of the fires were so fierce they began creating their own weather systems.

Almost 1,200 firefighters and two large air tankers were deployed to fight the blazes on Friday.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 50 seconds 50 s A wall of flames at Nymboida