'We're trapped': Firefighter's desperate radio call during bushfire

Three people have died and others remain missing following unprecedented bushfires that destroyed more than 150 homes across NSW.

Firefighters across the state have been stretched thin with recent emergency radio capturing the horrific moment firefighters were stuck, completely surrounded by fire after a burning tree fell in their path.

“That’s a negative — we have been trapped by a falling tree, over,” a firefighter can be heard over the radio to the operator.

“You have got all your protection gear in your vehicle? Your curtains and … sprinklers on and let us know how you’re going,” the operator said before calling in support.

“Copy that we are engaging protection,” the firefighter said.

The team manages to escape at the last minute.

“We have had to drive over the tree,” the can be heard saying.

A third person was confirmed dead on Saturday night after their body was discovered in a burnt-out building in the town of Johns River, about 40 kilometres north of Taree on the mid-north coast. Fires swept through the area on Saturday afternoon.

The home belongs to a 63-year-old woman although NSW Police say a post-mortem is needed to confirm the deceased's identity.

Wytaliba resident Vivian Chaplain, 69, was earlier named as one of the other victims.

She was discovered by firefighters with burns to 50 percent of her body and was treated before being transferred to hospital where she later died, RFS commissioner Shane Fitzsimmons said. It is believed she was trying to save her property when she succumbed to the blaze.

The body of an elderly man was found in a burnt out car near Glen Innes.

"We can't rule out the really grave concerns that there could be more losses or indeed more fatalities as we get through and identify details across these fire grounds," Prime Minister Scott Morrison told reporters in Sydney.

The prime minister says army reservists could be deployed "if necessary".

While they aren't trained firefighters, they could help create firebreaks away from the front or provide accommodation and logistical support, he said.

"These fires have already claimed two lives ... and as we get access to further areas that have been cut off we are expecting worse news again," the prime minister said.

Some 80 fires are continue to burn across the state with about 40 uncontained.

Three remain at emergency warning level at Hillville south of Taree, Stockyard Flat near Walcha and Nimbin north of Lismore.

There are 15 fires at the "watch and act" alert level.

Authorities have appealed to people to register both themselves and any loved ones they are concerned about.

The Red Cross says so far 1300 people have registered in eight evacuation centres across the state.

Glen Innes Severn Council mayor Carol Sparks says her community has been "badly impacted" with the loss of two people and "many of our houses (and) our school."

"We are so impacted by drought and the lack of rain," she told AAP on Saturday.

"It's climate change, there's no doubt about it. The whole of the country is going to be affected. We need to take a serious look at our future."

Nymboida RFS captain Paul Johnston told ABC TV he struggled to believe what he witnessed.

"It was an unprecedented event," he said.

"It was devastating. It was a storm. It wasn't a fire - it was a firestorm."

BOM meteorologist Katarina Kovacevic says while temperatures are cooler on Saturday, southerly winds tending southwesterly in the afternoon will gust up to 50km/h.

Conditions are set to worsen early next week, Ms Kovacevic told ABC TV.

Hot temperatures combined with low relative humidity and strong northwesterly winds will increase the fire danger on Tuesday and Wednesday in northern NSW and southeast Queensland.

The Public Information and Inquiry Centre (PIIC), remains open to assist members of the public in relation to bush fire information for the Northern Rivers, Clarence Valley, Mid North Coast, and Manning Great Lakes areas.

The telephone number to call is 1800 227 228.

Donations to The Red Cross Disaster Relief and Recovery fund can be made online or by calling 1800-RED-CROSS (733 276)

Do you have a story tip? Email: newsroomau@yahoonews.com.

You can also follow us on Facebook and Twitter, download the Yahoo News app from the App Store or Google Play and stay up to date with the latest news with Yahoo’s daily newsletter. Sign up here.