A search warrant was then executed. The woman has been taken to Maroubra police station where murder charges are expected to be laid.
Homicide squad commander Danny Doherty said the woman was known to Mr McCarthy and lived nearby.
“What I can say is that there is significant forensic and physical evidence to make this a strong and compelling case,” he said. “Mr McCarthy suffered severe head and facial injuries.
“It was a combination of physical violence and police will allege that in court; it was enough to kill Mr McCarthy.”
He did not speculate on a possible motive but added that Mr McCarthy’s family had been informed of the arrest.
“I think it’s mixed emotions for them. They have just gone through Christmas without a father and a grandfather. It is a point where any arrest is welcome … they are still getting over the grief of losing Peter.”
In December, Mr McCarthy’s son James said in a statement that his family was devastated and still coming to terms with the loss of their father and grandfather.
Mr McCarthy was last seen at Club York, on York Street in Sydney’s CBD, on the afternoon of December 16, between 12.30pm and 2.30pm. Detective Superintendent Doherty previously said the retiree frequented the venue at least three times a week.
He described Mr McCarthy as a “knockabout” man who “liked having a drink, liked having a bet down at the local” and was a well-liked man in his beachside suburb.
He said Mr McCarthy was a “gregarious person” who was always in contact with people, and for others not to have heard from him for a number of days was unusual.
Earlier, police released CCTV of a man and a woman whom they are asking to come forward. Detective Superintendent Doherty ruled out that the woman depicted in the footage was the one who had been arrested on Monday. He added that investigations into the pair were ongoing.
The man is described as being of Caucasian appearance, with a medium build and light brown hair. He is wearing black pants, black sneakers, a black Raiders singlet top and glasses.
The woman is described as being of Caucasian appearance, with a slim to medium build and light-coloured hair. She is wearing a black top, black hooded-jumper, black pants, black sneakers and a black face mask.
“I would like to thank the community for providing information to date but, at this stage, those persons haven’t been spoken to,” Superintendent Doherty said.
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Laura is a crime reporter for The Sydney Morning Herald.
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