The man allegedly behind the wheel of the Toyota Landcruiser that crashed head-on into Jenni Pratt's car on the Bussell Highway near Capel on Saturday has been identified as Shaun Southern.
The 45-year-old remains in a critical condition in hospital and is yet to be interviewed by detectives investigating the horrific fatal crash and his alleged erratic behaviour in the moments beforehand.
Homicide detectives are trying to determine why the father-of-two seemingly deliberately drove onto the wrong side of the highway, forcing dozens of oncoming motorists to swerve or drive their vehicles at high speed into roadside ditches to avoid a collision.
Ms Pratt was returning from an outing with a friend when her RAV4 was hit head-on by the 4WD Mr Southern was driving. She died at the scene.
According to Mr Southern's Facebook page, he lives in Busselton and lists his relationship status as single.
He has lived in caravan parks in Leeman and Bunbury.
Mr Southern went on an alleged run of terror on Saturday ending in a head-on crash near Capel that killed 61-year-old Ms Pratt.
Shortly before the crash he was seen by witnesses erratically leaving a South West beach, abandoning his belongings, according to Nine News Perth.
Nine News Perth reporter Michael Genovese, who was in the town of Capel on Monday, said investigators were trying to string together a timeline of events that led to the 20-kilometre rampage on the wrong side of Bussell Highway on Saturday.
Mr Genovese said witnesses told him Mr Southern had been at Wonnerup beach, about 20 kilometres from the crash site, when he suddenly left in a hurry.
"From what I've been told he left a camping stove and camping bed, some fishing gear and a table, phone and wallet all on the beach and just took off in a rush and that's where he started aiming at the other cars and a tree at one point," he said.
The horrifying footage of Mr Southern swerving onto the wrong side of the road in his green Toyota LandCruiser was captured by Dan Mateljan as he travelled with two friends in a car behind the 4WD.
Up to 20 vehicles were forced into ditches during the horrifying incident, which lasted several minutes.
Mr Mateljan was first at the scene of the head-on crash in which 61-year-old Busselton woman Jenni Pratt lost her life. Another woman, Ms Pratt's 54-year-old passenger, was pulled from the vehicle. She remains in Bunbury Hospital in a serious but stable condition.
"This dude is trying to kill someone for sure," Mr Mateljan can be heard saying on the footage.
Friends on Facebook paid tribute to Ms Pratt, remembering her as a loving mother who lived life to the fullest.
'She touched our hearts with her infectious smile and giggle," one friend said.
"Such a bubbly happy soul. RIP beautiful Jen," another wrote.
"Jenni was always the most beautiful soul. She loved life and loved her family fiercely.. So so sad to hear this news."
Police want to speak to anyone else who saw the crash or the Toyota LandCruiser before the accident at Wonnerup Beach, Busselton, Layman Road, Busselton or Bussell Highway from Busselton to the Capel Drive intersection.