'Absolutely horrific': Dozens of homes feared destroyed with two firefighters in comas

Two firefighters have been sedated while three others were treated for burns after their truck was “enveloped” by a blaze southwest of Sydney where authorities fear dozens of homes may have been lost.

Some 2500 firefighters are still battling more than 100 blazes with half of them uncontained.

NSW Rural Fire Service commissioner Shane Fitzsimmons on Thursday said two male firefighters – aged 36 and 56 – had been airlifted to a burns hospital with serious injuries, while a 28-year-old female was transported by road to hospital.

A further two firies were treated by paramedics for smoke inhalation after fighting the Green Wattle Creek blaze west of Bargo.

The commissioner said the crew was in one of many dozens of trucks in the area working to protect homes on Thursday when they were "overrun and enveloped by fire".

"Those injuries are reported to three people in particular – two males with face and airway burns and some other burns to different parts of the body such as arms, elbow, upper chest and a leg," Mr Fitzsimmons told reporters in Sydney.

"The third person, she is suffering some smoke inhalation and minor burns."

The RFS chief said the two male crew members were alert and conscious, "however given the serious potential for airway burns the advice is medically they'll be intubated".

Mr Fitzsimmons said the intubation was “precautionary” as “swelling can occur pretty quickly after the burn injury, and prevent breathing”.

“So intubation, I'm being advised, is occurring which means they'll be sedated and airlifted to hospital for treatment,” he said.

NSW Ambulance Inspector John Brotherhood said the situation was "absolutely horrific".

"It really proves how dangerous these fires are, how quickly things can change," he said in a statement.

There were also reports of "many structures and many buildings being impacted including some homes".

RFS deputy commissioner Rob Rogers says there are reports 40 buildings were destroyed, but it's unknown how many of those were houses.

"There's everything from people's homes, people's businesses, there are poultry farming operations... there are lots of buildings, including people's homes and livelihoods that have been impacted by this," Mr Fitzsimmons said.

“In the vicinity of dozens" of buildings had been destroyed, he added.

"What that is in terms of homes, sheds, facilities – I just simply don't have that detail at this stage. It's too fast and unfolding as we speak,” he said.

The Green Wattle Creek blaze was one of two fires at emergency warning level on Thursday afternoon.

‘As bad as it gets’

A volunteer NSW RFS firefighter told The Sydney Morning Herald crews had performed “courageously” against the blaze which is currently more than 156,000 hectares in size.

“This is as bad as it gets. We've had gas cylinders exploding, very, very intense fire activity,” the volunteer told the publication.

“We're doing as much as we can now to try and save lives.”

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AAP has been told more than 20 homes may have been destroyed in and around the village of Balmoral.

Nine News captured what appears to be a firefighting aircraft taking water from a swimming pool to fight fires.

Residents in Bargo, Yanderra, and Balmoral as well as Pheasants Nest, Buxton, Couridjah, Thirlmere and Tahmoor have been told it's too late to leave.

"Seek shelter as the fire approaches," the RFS warned at 3.30pm (local time).

A week-long state of emergency has been declared for all of NSW.

A total fire ban is in place across all of NSW and extreme fire danger in the Illawarra-Shoalhaven, southern ranges and Greater Sydney areas.

An evacuation centre at Picton Bowling Club – which has a capacity of 300 people – is completely full.

Wollondilly Shire Council mayor Matthew Deeth says the club's car park is "pretty much dogs and cats as far as the eye can see".

"We're a semi-rural community so we have a lot of livestock that has been needed to be moved quite quickly," Mr Deeth told AAP, adding residents were very anxious.

"There are a lot of people feeling concerned about their properties, we've had quite a number of properties that have been lost today and there's been about six properties lost previously."

Multiple roads closed across NSW

As of 7.40pm (local time) on Thursday, 17 roads across NSW had been shut due to the fires.

Multiple roads from Lithgow to Kurrajong had been closed due to the Wollemi fire.

The Hume Motorway between Campbelltown and Mittagong, and Picton Road were previously closed due to a bushfire, but have since reopened.

For the latest information about road closures due to fire activity, visit Live Traffic NSW’s website.

With AAP

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