A man allegedly attacked his sister with a sword, resulting in her critical condition, before he was fatally shot by police at a residence in outer Melbourne.

Currently, an investigation into the 45-year-old’s death is ongoing, while his 48-year-old sister remains in a coma in the hospital after sustaining a partially severed arm from the incident.

The situation began around 5.30pm yesterday when two officers were dispatched to a property on Warburton Highway in Yarra Junction, approximately 55km east of Melbourne, following their mother’s call to triple-zero reporting the siblings’ altercation.

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.

“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 looking into the death with oversight from the Professional Standards Command, as is customary following a police shooting.

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