A 33-story apartment high-rise near central Sydney was evacuated Monday after residents reported hearing cracking noises.
More than 140 residents of the Opal Tower in Sydney's Olympic Park were forced from their homes along with occupants of nearby houses.
Train stations and roads near the building were closed while New South Wales state fire and rescue personnel assessed the structural integrity of the building.
Aerial footage showed firefighters setting up tents around the building and redirecting pedestrians.
New South Wales police said in a statement that several residents left the building in the morning after hearing "cracking noises."
Meriton, the operator of the neighbouring building, said in an email to residents that there was "potential for the tower to collapse."
A resident of the Opal Tower told the Nine News network he heard a loud bang as if something in the building had "snapped."
"A few days ago the doors looked different, like they couldn't close properly. And you do feel (movement) sometimes when there's strong wind."