One person arrested after woman fatally falls from Sydney unit

Police have arrested a woman and seized a car after another woman was found dead on the footpath beneath a Sydney unit building.

NSW Police at the scene where a woman died at a unit block in Zetland, Sydney on Tuesday, June 18, 2019. Source: AAP

Police have arrested a woman near the rugged coastline south of Sydney after another woman plunged to her death from an inner-city unit block.

The 23-year-old was discovered with critical injuries on a footpath at the back of the 11-storey complex on Rose Valley Way in Zetland about 8.45pm on Monday.

Emergency services were called but she could not be revived.

The 23-year-old was discovered on a footpath at the back of the 11-storey complex. Source: AAP

Police on Tuesday appealed for help to find 29-year-old Zixi Wang, also known as Jessie, who was wanted on an outstanding arrest warrant in relation to the incident.

Ms Wang had been last seen in a white Mercedes Benz and was considered to be in a "vulnerable state".

"She'll be able to establish what possibly could have happened at the scene," Superintendent Bradley Hodder told reporters in Sydney.

"However we're concerned for her welfare as well. We'd like her to come forward ... My message, my strong message, would be for her to go to the nearest police station and hand herself in."

Police say they found a white Mercedes at Sea Cliff Bridge, north of Wollongong, on Tuesday afternoon.

A 29-year-old woman was arrested nearby.

The scene where a woman was found fatally injured at a unit block in Zetland, Sydney. Source: AAP

The car was seized for forensic examination.

Police were doorknocking surrounding homes and combing gardens at the unit complex where the woman's body was found.

At the back of the building a badly damaged white steel fence, below a number of balconies, were cordoned off with police tape.

"It was a horrible scene; any of these sort of falls from buildings are a tragic sight," Supt Hodder said.

Residents from the unit block on Tuesday told News Corp Australia they had heard a someone screaming before her body was discovered.

"My friend came over and she heard it in the hallway when she came into our apartment ... she literally said 'it sounds like someone's dying in there'," one said.

A 29-year-old woman has been arrested and is assisting police with inquires. Source: AAP

"Just screaming, so it sounded like someone young or a female."

Supt Hodder said those reports would form part of the police investigation.

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