More than 120 firefighters battled the blaze at the multi-level building.
Multiple calls to emergency services were received when flames started engulfing the seven-storey building on Randle St just after 4pm, Fire and Rescue NSW said.
Firefighters from 30 fire trucks and multiple stations were involved and at least one firefighter was injured.
Dramatic video showed a huge section of the building collapsing.
“A tornado of black smoke has blanketed the area,” another witness told news.com.au yesterday. “The building looks like the bottom of a fire pit.”
Fire and Rescue NSW acting commissioner Jeremy Fewtrell told a press conference: “It was an incredibly intense fire.”
It reached a “10th alarm” status, which is the most severe type of fire.
Fire and Rescue NSW superintendent Adam Dewberry told Sunrise this morning that there was now a “major concern” that the building could collapse.
“There is a high chance these could fall in, collapse without notice, bringing tonnes of bricks down, those bricks becoming projectiles,” he said.