Homicide detectives are investigating after a 37-year-old man was arrested following the death of his partner, who was found seriously injured in a home in Perth's south-east.
Emergency services were called to a residence on Knutsford Avenue in Kewdale at 7:45pm on Monday.
Police and St John Ambulance officers administered first aid to the 35-year-old woman and she was taken to Royal Perth Hospital, where she later died.
At a media conference, police confirmed the deceased woman and the 37-year-old man who was arrested were partners who lived together.
They have two children and police say they were present in the family's Kewdale home where the woman was found badly injured yesterday evening.
Police said she had been assaulted and her injuries were consistent with a weapon being used.
The man is under police guard in hospital receiving treatment for non-life threatening injuries he suffered when he crashed his car on Berwick Street in St James.
It is alleged he fled the scene and was arrested by police in the yard of a nearby home.
Detectives are yet to formally interview him.
Police say the two children, who police also hope to speak to, are being cared for by family members.
Investigations are examining whether the events are linked to an armed robbery on a service station in East Victoria Park.
A neighbour described feeling alarmed when she saw a woman run out of her house and into the street screaming.
"The screaming, the immense screaming, the wailing ... is the first thing we heard before the police sirens," she said.
"She ran out into the front of the house and into the street, then back into the front of the house screaming ... and then the kids came out with her, and they were saying 'there's a knife ... there's a knife'."
Man runs into house after crash
Police say the man then crashed his Ford dual-cab ute on Berwick Street at the intersection of Emily Street in the nearby suburb of St James.
Another resident said the man then came into her house and grabbed a knife from her kitchen after crashing the car.
She said the man "unbelievably" managed to free himself from the "very badly damaged" vehicle before he approached her family for help.
She said the man followed her into her house, despite her son trying to block his path.
"We just believed he's in shock, so I [took] him through [to] the kitchen.
"He has put the tap on and he's washing his eyes and my son notices him grab a knife from the pot soaking ... on the sink."
Another resident on the street said he also saw the man get out of the vehicle, before he entered the home asking for help.
"He was saying that his eyes are burning, and he needed some assistance," he said.
The man was arrested at a nearby residence at 8:20pm and was taken to hospital where he remains under police guard.
Police are also investigating a possible link between this incident and an armed robbery at a nearby service station on the corner of Kent and Berwick Streets in East Victoria Park.
Police are yet to lay any charges against the man.
