Residents have recently been allowed to return home after the authorities came up with a solution to remove the collapsed crane the fell on to an apartment complex.

An investigation has been underway regarding the cause of the incident, which damaged a nearby unit block on Brodie Spark Drive at Wolli Creek on Sunday. Authorities said around 160 residents of the damaged building had to spend another night in temporary accommodation. However, another 300 residents of the surrounding blocks were allowed to go home on Sunday Night.

The crane was yet to be removed and power at the damaged building was still unavailable, Fire and Rescue NSW spokesman Superintendent Josh Turner said.

“The crane’s been stabilised so it is safe for workers to actually get access,” he said.

“Residents are still outside of the building as we have got power and gas cut off as some of that was damaged through the fall of the crane.

“So it is safe for workers to enter and a strategy is being developed to start dismantling the crane.”

The early investigations indicated that it was a mechanical or engineering mistake with the crane that led to the collapse, Construction, Forestry, Mining and Energy Union (CFMEU) NSW state secretary Brian Parker said. CFMEU is urging the authorities not to remove the crane until the investigations are completed.

“Our fears are not just for the workers that work to erect these cranes, but also the public.” he added.

Mary Broadley, a resident of the unit where the crane was stuck, said she thought the entire building would collapse. “It was so noisy, it was just unreal the noise,” she said. The ceiling and walls of the bedroom of the flat had cracked and windows had smashed.

The accident saw three construction workers sent to a hospital for treatment, one of them with a suspected broken leg.