Man shot dead by police after allegedly attacking his sister with samurai sword

A man allegedly violently assaulted his sister with a sword, leaving her fighting for life, before he was shot dead by police at a home in outer Melbourne.

Today an investigation is continuing into the 45-year-old's death, while his sister, 48, remains in a coma in hospital after suffering a partially severed arm from the attack.

Events began about 5.30pm yesterday when two officers were called to a property on the Warburton Highway in Yarra Junction, about 55km east of Melbourne after their mother called triple-zero, saying the siblings were fighting.

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When police entered a bedroom, they found the man strangling his sister who had a partially severed arm.

Officers deployed their tasers three times to try and stop the assault, but the man continued to strangle the woman.

One of the police then fired their gun, killing the man.

Police said the man had a history of mental health issues. A samurai sword was found inside the home.

Victoria Police Assistant Commissioner Russell Barrett said today the officers were confronted with a distressing scene.

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"Police are still searching the premises," he said.

"Obviously, if I can convey, it's a very graphic and dramatic scene when they walk in. He is strangling the female and the arm is partially severed."

Ambulance crews were called to the scene but the man could not be revived.

The woman was flown by air ambulance to hospital and is being treated for serious injuries. She remains in critical condition early today.

Homicide detectives are investigating the death with oversight from the Professional Standards Command, which is standard practice in a police shooting.

The State Coroner, Judge John Cain, also attended the scene.

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