Police have evacuated four unit blocks after a crane crashed onto a penthouse in Sydney's south this morning.
Three people were injured when the structure toppled from one building onto another at Brodie Sparks Drive, Wolli Creek.
Two were taken to St George Hospital, one suffering from a leg injury.
Photos from the scene show the crane resting on the penthouse of the apartment complex which sustained substantial structural damage.
Four buildings are now at risk and have been evacuated as police establish an exclusion zone, with hundreds of people told to leave with fears the crane could fall.
Road closures are in place while no trains are running between Central and Turrella on the T2 Airport Line. Buses have been arranged to transport people between Sydenham and Central.
Wolli Creek resident Felicia Nguyen, who lives in the building opposite to where the crane came down, said they just had time to grab some personal items.
"They told us that when they rescue the crane it might fall into my building so we were evacuated us until the rescue team gets here and can start work but we don't know how long that will take," she said.
Ms Nguyen said she was having breakfast when she heard the crane collapse just after 9.30am.
"We heard the crashing sound we went to the door and the white crane just feel down.
"They were setting it up and it seemed to fall into the penthouse of the building next door.
"It was really loud, it was like something had dropped from the top floor, all the glass fell from the top floor, from the penthouse, the windows fell out and about 5m of the balcony all fell to the road below and it's now blocking it off.
"I hope there was nobody in the penthouse, I couldn't see anyone.
"When the crashing sound happened I saw all these people all raced out the back door (of the building) because they couldn't go out the front and look up to see what happened, then they were told to evacuate.
"Other people were shopping and the came back and it was blocked off and they had to leave," she said.
SafeWork NSW has been advised and will investigate the incident.
It is expected the exclusion zone will remain in place for some time.
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