Police reportedly believe the apparent attacker - who was apprehended by members of the public yesterday in a tense CBD showdown - slashed the woman's throat with a butcher's knife.
The police believe the attacker then fled the scene to commence his six-minute knife-wielding rampage in the heart of Sydney's CBD.
According to the Daily Mail, detectives are currently going through the victim and the perpetrator's phones to establish the nature of their relationship. According to reports, she was believed to be a sex worker.
Footage captured police carrying the woman's body out of the Clarence Street building early Wednesday morning.
New South Wales police commissioner Mick Fuller said in an official statement the attacker was visiting the victim for 'business purposes'.
"It appears he was there for a business purpose."
There were shocking and terrifying scenes in Sydney’s CBD yesterday afternoon, with a man detained by members of the public following an alleged knife rampage.
While the man was reported to be shouting religious slogans, the Daily Telegraph is reporting that he is 'believed to be an escaped mental patient'.
Vision captured at the scene shows a man on top of a car at a city intersection, waving a knife, before he falls to the ground as the car moves away. He is later heard asking to be shot.
Police were dispatched to King and Clarence Streets in the CBD, but it is believed members of the public detained the man ahead of their arrival.
Later vision, shown by Seven News, depicts the man pinned under a café chair by multiple men. A distressed witness at the scene is heard admonishing the man for ‘stabbing a chick’.
The alleged perpetrator is shown with blood on his hands and is seen relatively motionless, pinned under the chair with a milk crate over his head.
A police statement advised:
'That male offender, which we will be alleging is responsible for the stabbing is now in custody.
'All I can conclusively say is that male offender was on his own and there was no person complicit at this stage.
'We don’t know the causation or the rationale for his actions today.'
Police allege the man had attempted to stab multiple people. The status of the one currently-confirmed victim has been described as stable.