Thomas said the stepson – who was known to police – was not living at the Hillside property and “showed up unannounced” on Friday morning. Thomas said active intervention orders were in place against him.

Thomas said he had seen the officers’ body-cam footage and it “appeared [they] have done everything they could” to defuse the situation.

The stabbing victim’s 27-year-old daughter – who is pregnant – was taken to hospital for observation, police said.

Police are investigating the incident. Homicide squad detectives will examine the 61-year-old man’s death, while the armed crime squad will investigate the confrontation with the stepson with oversight by Victoria Police’s Professional Standards Command, as per protocol when a police firearm is discharged.

Anyone with information is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au.