The search operation for a woman, trapped in the rubble of her townhouse in Sydney’s west following an explosion, has continued overnight.
But the Fire & Rescue NSW commissioner admits it would be “very challenging” for someone to have survived the blast.
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Rescue crews searched through the night for the woman in the collapsed townhouse complex on Waikanda Cres in Whalan, following the explosion just before 1pm on Saturday.
The blast levelled most of the two-storey home, blowing out windows and damaging a neighbouring townhouse.
It was heard several suburbs away and destroyed a two-storey townhouse in the social housing complex for over 55s, causing “widespread damage” to neighbouring properties in the complex.
Five people were treated for minor injuries following the blast, including two women in their 60s and 70s, one of whom was in a wheelchair. A dog was also rescued from the ruins.
Three people were taken to Mount Druitt Hospital, while two others were taken to Hawkesbury District Health Service.
A woman, understood to have been in a second-floor unit at the back of the home when the explosion occurred, is still unaccounted for.
A search operation to locate her continued through the night.
Searchers heard tapping from underneath the rubble, but 7NEWS understands this has stopped.
Fire & Rescue NSW are searching brick-by-brick through a targeted area, though they are being hampered by wet weather.
“Crews have worked through torrential rain,” Fire & Rescue NSW Commissioner Jeremy Fewtrell told Weekend Sunrise.
“They’ve moved a large amount of debris, they’ve been exploring and searching any little cavity.”
Crews are now preparing to move larger parts of the debris to gain further access, he said.
“At the moment we have a person unaccounted for, and we’re taking every possible effort to search the remnants of the building,” Fewtrell said.
“You can see from the footage how totally destroyed that property is.
“There’s four apartments, four units in that block that have collapsed — all the parts of that unit have fallen down.
“The crews have had to work their way through the different layers of that building to try and fully examine any possible areas.”
There is still an extensive area to be searched, Fewtrell said.
The operation is still being classified as a search operation, he said.
“However, it would have been a very difficult scene for someone to have survived from, both the explosion … and it was a very large explosion … and then the physical impacts of building parts falling down,” Fewtrell said.
“It would be a very challenging scene for someone to have survived.”
Emergency services are yet to establish what caused the blast, which will be subject to a NSW Police investigation.
Police were initially called to reports of a gas explosion.
Gas mains were isolated at the property on Saturday so crews could safely step up their search and use concrete cutters to remove the debris.
– with AAP