A search and rescue operation was launched at a collapsed townhouse complex in Whalan, in Sydney’s west, on Saturday afternoon.
An explosion on Waikanda Cres just before 1pm prompted the immediate evacuation of a number of people, with one person still unaccounted for.
WATCH THE VIDEO ABOVE: Major explosion at Sydney townhouse complex sparks emergency operation.
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“There has been a major explosion in the townhouse complex,” Fire and Rescue NSW told 7NEWS.com.au.
“There is a lot of damage to the second level of the unit.”
Six people have been evacuated from the building and assessed at the scene by paramedics, NSW Ambulance confirmed.
Three patients were taken to Mount Druitt Hospital and three were taken to Hawkesbury Hospital.
“Firefighters and other first responders have rescued two people, a woman in her 60s, and a wheelchair-bound woman, in her 70s, from the ruins and have commenced a search and rescue operation to determine if others are trapped in the rubble,” FRNSW said.
One section of building appears to have been completely flattened, in images from the scene.
“The large blast blew out windows and damaged neighbouring townhouses in the multi-apartment complex,” FRNSW said.
“The gas company has been unable to cut off supply to the scene and is attempting to isolate the mains.
“There is no fire at present but the scene remains volatile and unstable.”
FRNSW has more than a dozen units at the location, including rescue, HAZMAT and ladder platform appliances. Drones are also in use to make an aerial assessment of the blast zone.
The public has been urged to avoid the area, as the emergency operation remains ongoing and local traffic diversions are in place.
NSW Police are investigating the explosion.
