The 24-year-old lady from regional Western Australia was discovered unresponsive in a carpark at Wellington Street, close to Pier Street, simply earlier than 3am.
Emergency companies tried to revive the younger lady however she died on the scene.
A 27-year-old man, who can be from regional WA, was arrested in Perth’s CBD a short while later and helps police with the investigation.
Detective Senior Sergeant Keith Neubronner mentioned the 27-year-old man and sufferer have been identified to one another and had a “domestic relationship”.
Neubronner mentioned the lady had been assaulted however there have been no apparent accidents.
He added the assault started at Yagan Square and “went all the way down to Wellington Street” the place she collapsed and died.
Neubronner mentioned there may be intensive CCTV between the 2 areas to indicate what occurred and police shall be amassing it immediately.
“We need to look at the footage and ascertain what happened,” Neubronner mentioned.
Prior to the assault, Neubronner mentioned there was a big group of individuals socialising in Yagan Square however nobody noticed the alleged assault of the lady.
Witness Lesley Hill advised 9News he was sleeping tough when he noticed a big celebration of individuals stroll previous.
“They were all happy and drinking,” he mentioned.
“They went down towards McIver Street, but at this point all the men were gone and only five women came back from McIver.
“They sat down on the curb. She could not stroll any additional, she sat down, fell over and died proper there.
“The group started screaming, yelling, all the women were crying.”
Homicide detectives at the moment are on the scene and have cordoned off two areas with police tape.
Anybody with data, or who has cell phone or dashcam footage of the world between 2.30am and three.15am, is urged to contact police.