Firefighters work into the night on massive Sydney CBD blaze
Fire and Rescue NSW crews are working into the night to extinguish the massive inferno that destroyed two multi-storey buildings in Sydney's Surry Hills.
Crews were expected to keep working Friday morning to get rid of all remnants of the blaze before investigations into how the fire started can begin.
Fire and Rescue NSW Commissioner Jeremy Fewtrell told media on Thursday evening it could take "several hours" to put out the fire completely.
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"It will be a substantial and very prolonged duration of firefighting, to extinguish the fire completely," he said.
The massive inferno — dubbed a "10th alarm", the most severe type of fire — sent plumes of smoke drifting over the city and shut down nearby streets as the heritage-listed former hat factory at 11-13 Randle Street started to collapse.
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Hundreds of people were evacuated from the area as the fire burned through several levels on Randle Street near Central Station just after 4pm on Thursday.
More than 100 firefighters were called to the scene from multiple stations across Sydney, needing hours to contain the blaze with a combination of aerial and ground attacks.
Fewtrell said there were "collapse zones" in place to protect firefighters as they kept working.
"We have some engineers attending the scene and they'll help guide our decisions around safety considerations particularly around the risk of collapse," he said.
Once the fire is finally extinguished, investigators from both FRNSW and NSW Police will enter the scene to determine the cause of the blaze.
Both organisations said it was too soon to speculate.
"Our fire investigators along with police forensics will start to make those assessments but that will be sometime downstream," Fewtrell said.
John Duncan from NSW Police said the matter was still under investigation.
"We will work with their investigators to work out what actually occurred. It's way too early [to say what sparked the blaze]," he said.
Fewtrell asked anyone with information or video to come forward.
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