Police have charged a man after an assault in Mandurah on Thursday night.
At around 8.45pm, police were called to a house on Forward Street, where they found a 45-year-old man allegedly assaulting a 43-year-old man.
The two men were separated and the alleged offender was arrested.
Officers provided immediate first aid to the victim, including CPR, before he was taken to hospital.
The victim remains in a critical condition at Sir Charles Gairdner Hospital.
The 45-year-old has been charged with attempted murder and will appear in Perth Magistrates Court on Friday.
Anyone who may have witnessed the incident or been in the area at time, has dash-cam footage of the area at the time, or has any information is asked to call Crime Stoppers on 1800 333 000 or report online at www.crimestopperswa.com.au.
Police said the men are known to each other and this is an isolated incident with no ongoing risk to the community.