A woman has been arrested on the Sea Cliff Bridge following the suspicious death of another woman believed to be her ex-girlfriend outside a Sydney unit block on Monday night.
Emergency services were called to Rose Valley Way at Zetland, in Sydney's inner east, about 8.45pm after a woman was found injured at the rear of a unit complex.
Police officers attempted to revive the 23-year-old woman but she died at the scene.
On Tuesday, police released images of 29-year-old Zixi Wang - also known as Jessie - who they said might be able to assist with inquiries.
Police said she had an "outstanding arrest warrant in relation to the incident".
The registration of a white Mercedes was also released as part of the appeal for information.
Following a tip-off from the public, officers found a white Mercedes at the Sea Cliff Bridge, north of Wollongong, about 3.30pm.
A 29-year-old woman was arrested near the vehicle and is assisting police with inquiries.
The car has been secured for forensic examination.
Police said no further information was available at this time.
Strike Force Deepfield has been set up by Redfern Police Area Command detectives to investigate the incident.They are being assisted by the State Crime Command's Homicide Squad.
Botany Bay Police Area Command Commander Superintendent Bradley Hodder had earlier told reporters that Ms Wang might "be able to help establish what possibly happened at the scene".
"We're concerned for her welfare as well and we'd like her to come forward," he said.
"I believe she's in a vulnerable state."
She was last seen in a white Mercedes-Benz driving away from Rose Valley Way.
The circumstances leading up to the 23-year-old victim's death are unknown, however the SMH reports she had suffered injuries before being found on the concrete outside the 11-floor apartment block. A nearby fence showed signs of significant damage.
Police have seized a computer from the apartment, which will be taken for forensic analysis.
On Tuesday morning, residents of the apartment block told reporters they heard a woman screaming before the body was found.
Anyone with information should contact Crime Stoppers on 1800 333 000.
- with AAP