The son of a woman who was allegedly murdered by her partner has questioned the one-hour delay in the police response as his mother lay unconscious on the floor.

The woman has been identified as Casino mum-of-three Sarah Miles.

Miles was unconscious but breathing when officers arrived at her home in the Northern Rivers region, about 2.27am on Saturday after receiving a call over welfare concerns.

She had “obvious injuries” to her head caused by a physical assault, NSW Police Assistant Commissioner Peter McKenna said.

“Police assisted her and called for an ambulance immediately. [It] arrived very shortly after but unfortunately her condition deteriorated and she died at the scene.”

Miles’ son Shayden Miles paid tribute to his mother in an interview with Channel Nine.

“Words cannot describe the pain that I am feeling at the moment,” he said.

“My mother was a very strong person, [a] fighter always to the end.

“I’m so proud of her and I’m proud, I’m proud to have her as my mother and I’m proud to have been her son.”

Shayden Miles says his mother was on the floor for an hour. Photo: Nine Network

He questioned the time it took police to arrive at the scene.

“It’s not just a loss, it’s also dealing with the fact that she was waiting for an hour on the floor and that is something that will stay with me for the rest of my life,” he said.

The woman’s partner has been charged with murder.

The 31-year-old man was arrested at the scene and taken to Lismore Police Station, where he was subsequently charged. McKenna said the man was believed to have been in a relationship with Miles for some months, McKenna said.

A crime scene was set up and a regional critical incident team will investigate all circumstances surrounding the case, including the police response.

A triple-zero call was made just after 1.30am but it took until 2.25am for police to acknowledge the call. Officers in Casino arrived at the scene two minutes later, McKenna said.

“The delay in the timing of police acknowledging that call and attending the scene has given me enough concern that I’ve asked for an independent review of this investigation as to what that delay was and if it was justified,” he said.

“We want to see what happened from the time that call was made, how the radio operator dispatched that call, the circumstances around the timings till it was acknowledged and until police attended.”

The independent critical incident probe will look at whether the call was allocated the right priority and if it was acknowledged as such.

Homicide squad members are separately working with local officers to investigate the woman’s death.

McKenna said police took domestic violence seriously and the issue was at the “top of our priority list”.

“It is one of the most serious crimes there is and we will do everything we can to take this as seriously as we can and make sure people are held to account and put before the courts,” he said.

1800 RESPECT 1800 737 732

Lifeline 131 114