WA murder accused remains in psych ward

A hospital order has been extended for a 23-year-old man charged with the murder of his father and a neighbour who intervened during a fight in Perth's northern suburbs.

Rainer Stefanski, 69, was left in critical condition after the assault at his Woodvale house on Saturday and died on Monday night.

His 68-year-old neighbour, Bill Butler, died at the crime scene.

Jason Stefanski appeared briefly in Stirling Gardens Magistrates Court on Wednesday via video link from the Frankland Centre, a psychiatric ward at Graylands Hospital.

Stefanski was previously placed on a hospital order and the magistrate said she would extend that order for both charges.

He is due back in court on September 17.