Police have made a breakthrough in a Sydney cold case murder, arresting a woman for allegedly killing her mother nearly 18 years ago.

A 45-year-old woman is expected to be charged over the murder of Irene Jones, who was found dead in the kitchen of her home in Sydney's south-west in 2001.

Police said they will allege the daughter had a financial motive to murder her mother and she inherited and sold the Lansvale home.



The body of Ms Jones, who was 56 at the time, was discovered by police officers responding to reports of a break and enter at a Lansvale home.

A post mortem found Ms Jones had been strangled and stabbed in the neck.

Irene Jones, 56, was allegedly murdered by her only child. ( Supplied )

Police will allege her daughter staged the murder to look like a break and enter and went to a neighbour's house where she called triple zero.

Local police initially launched an investigation and her daughter was a suspect, but no one was ever charged over her killing.

In 2007, a NSW coroner referred the case to cold case investigators who re-opened the probe in 2017.

Detective Inspector Stewart Leggat from the Unsolved Homicide Squad said the 45-year-old mother of three was "stunned" when detectives arrived to arrest her in Bondi this morning.

He said it "feels really good" to progress the case after almost two decades.

"It was just a matter of reviewing the case and looking at the available evidence," he said.

"Obviously there's improvements in forensics ... and forensic sensitivity in regard to DNA."

Detective Inspector Leggat said police also re-interviewed original witnesses.

The 45-year-old woman is currently at Waverley Police Station.