Police said neighbours tried to assist but were unable to access the building because of the flames.
The family members were taken to Nepean Hospital with smoke inhalation and minor injuries, a NSW Ambulance spokesman told NewsWire.
Police confirmed two bodies – one upstairs and the other on the ground floor – were found inside the home.
The bodies are yet to be formally identified but are believed to be the missing children.
Family due to relocate day of fire
The family of six were planning to move to Queensland the day of the fire, police said, and the mother had already left before the fire ripped through the house.
“The family were due to relocate to Queensland today,” Superintendent Roberts said.
“Mum was not inside the house at the time – it was just dad.”
The mother is now rushing back to the Blue Mountains to reunite with the family.
Superintendent Roberts said the incident was “incredibly confronting”.
“It’s an incredibly confronting situation, not only for the community and the families but also the first responders who had to attend,” she said.
Police not treating fire as suspicious
The fire raged for about two hours, with four fire trucks and 16 firefighters from the NSW Fire and Rescue, working alongside multiple Rural Fire Service crews, energy authorities and SES volunteers.
About 50 firefighters were needed to bring the blaze under control by about 3.30am, with crews staying at the scene until 5am to ensure the blaze was fully extinguished.
Police are yet to determine the cause of the fire but are not treating it as suspicious.
‘Too dangerous’: Intense fire causes roof to collapse
NSW Rural Fire Service commissioner Trent Curtin earlier said the damage caused by the fire made the search more difficult for firefighters.
“There are parts of the home that are still hot and smouldering, and many parts of the home have collapsed, so firefighters are moving into the home with hose lines to gain access to areas where they can search for the unaccounted people in the home,” he said.
He told reporters drones and a canine detection dog were being used to locate the two missing children because of the “very, very dangerous” state of the building.
“Firefighters’ dynamic risk assessment would have shown them that it would be too dangerous to go inside the home while it was collapsing,” he said.
“This is a two-storey home, and so it would have been very, very dangerous for firefighters to access the home in the early stages with the home fully engulfed in flames.”
He said the fire had affected the small town and was “very tough” for the firefighters.
“[It’s] very tough for our firefighters … all of those firefighters are impacted by the circumstances,” he said. “This is a very close-knit community.”
Tight-knit community rallies together
Residents from the tight-knit community are raising funds for the family following the tragedy.
Natasha Holden started a GoFundMe page to “rally together support” for the family affected by the fire.
“In times like these, our community’s strength shines brightest,” she said.
“Together, we can provide comfort and support during this incredibly difficult time.”
Macquarie MP Susan Templeman offered her sincere condolences to the family, residents and first responders.
“News of two deaths and others taken to hospital after a house fire at Bowen Mountain is deeply distressing,” she shared on social media.
“Sincere condolences to the family and local residents in this close-knit Bowen Mountain community.
“And, of course, our respect and appreciation to firefighters from multiple RFS brigades and other emergency services who attended the fire.”
Hawkesbury City councillor Mike Creed said it was absolutely devastating.
“My heartfelt condolences are with the family and loved ones of those lost,” he said.
“I’m also thinking of the man and children who escaped and our first responders who attended such a tragic scene.
“Our community will wrap around those affected in the days ahead. Please keep them in your thoughts.”
Anyone with information about the fire is urged to contact Crime Stoppers on 1800 333 000.
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