THREE children have died and several family members rushed to hospital after a home went up in flames in Singleton overnight.
Emergency services received numerous triple-0 calls to the property on Brittliffe Close about 3.30am Wednesday.
On arrival at the scene crews found the house well alight and support vehicles were called in to help.
The roof of the home had collapsed in the blaze and several people were trapped inside.
Crews managed to rescue many of the family members who were rushed to Singleton District Hospital in a critical condition.
A 31-year-old woman and an eight-year-old girl were treated by paramedics at the scene for smoke inhalation, before being taken to John Hunter Hospital. Both remain in a stable condition and are receiving treatment for burns. The female, mother of the family, suffered burns to her back and forehead.
There were grave concerns for one child, with crews searching for the missing 11-year-old boy for some time. In tragic news, the child was found deceased inside the property.
Police have since confirmed that two girls, twins aged five, were taken to Singleton Hospital but were pronounced dead as a result of their injuries.
Shandelle Reid, 27, a nearby resident, was awoken by a torch at one one of her windows during the night.
She said by that stage, the street was lined with emergency service workers and neighbours.
"I was woken up because I heard yelling and screaming," she said.
"There was the fire brigade, the police - who were actually directing people away from the live wire that was hanging from the power line.
"There was heaps of people, the whole area was crowded."
Ms Reid said the flames were "skyrocketing out of the roof" and there was a big "bang, a big explosion" when part of the house collapsed.
She said neighbours had attempted to help during the fire.
"This lady, she went into help. She said she pulled one of the kids through the back window," she said.
"But the frame collapsed in and she said she couldn't get in there to get the other kids.
"But she said she kept hearing them screaming."
Ms Reid described the neighbours who assisted "pretty brave, to run into a burning house".
Emergency services are expected to remain on scene for some time.
Police have commenced an investigation into the circumstances surrounding the fire.
"I would like to emphasise the heroic nature of the four residents in the nearby vicinity that tried to assist the people inside the house and importantly got the mother and the eight-year-old daughter out," Hunter Valley Police District Commander Superintendent Chad Gillies said at a press conference on Wednesday.
"We're now working closely to manage the welfare of all our emergency service workers that were involved in today's tragic incident."
Superintendent Joshua Turner from Fire and Rescue NSW said crews arrived on scene to find neighbours valiantly attempting to douse the flames with garden hoses. Crews immediately got to work and attempted to rescue the family trapped inside the home.
"They made entry through the front door but unfortunately the heat and intensity if the fire forced them back though the front door and have to go into defensive mode and fight the fire from the outside," he said.
"Back-up crews made access to the side of the house and were able to make entry through side windows to two bedrooms that weren't yet completely involved with fire and assist with removing two persons from those two bedrooms.
"Two people had previously been removed and were being assisted by ambulance."
Risk of structure collapse and the intensity of the flames meant further internal rescue attempts could not be made.
When it is deemed safe to do so, police and fire investigators will examine the home to identify where and how the fire started.
At this stage, Superintendent Turner could only confirm that the fire started at the front of the home and travelled through to the rear of the property.
"We have seen, particularly in this area, in the last few weeks a large number of fires have been caused through heating appliances and so forth, and coming into winter that is a major contributing factor to fires," he said.
"Knowing there was a fireplace in the vicinity, it will be a major point of investigation."
Police will prepare a report for the coroner outlining the full circumstances surrounding the incident.
While the Singleton community remains in shock from the early-morning news, messages of support for first responders are already pouring in from Fire and Rescue units across the Hunter Region.
"As firefighters, its a reality that can turn into a nightmare," a statement from Fire and Rescue NSW Station 344 Kearsley said.
"Responding to a fire and having persons reported as missing or still inside. We stand strong beside our mates at 444 and all responding crews knowing that this incident is having a huge impact on them all."
The Abermain crew said "feelings are high for the guys at 444, tough few weeks".