A woman is fighting for life with a partially severed arm after an assault by her brother, who was shot dead by police during the attack.

Police were called to a home on the Warburton Highway in Yarra Junction about 5.30pm on Wednesday following reports a man was assaulting a woman.

A man was shot dead by police in the Yarra Valley on Wednesday afternoon.

Eastern Region Assistant Commissioner Russell Barrett said the siblings’ mother reported the violent fight between her two children, who were both aged in their 40s.

Police were met outside the home by the pair’s mother, who told police her son had a mental health condition. Screaming could be heard coming from inside, Barrett told reporters on Thursday morning.

“[Police] then entered the bedroom and were confronted by a female who appeared to be unconscious and appeared to have a limb that was partially severed, being strangled by a man,” Barrett said.

Officers deployed their tasers three times in an attempt to stop the assault, but the man continued to strangle his sister. One of the officers then used their firearm, fatally shooting the man.

Police entered the home to find a woman being strangled by a man.

“It’s every police officer’s nightmare,” Barrett said. “Both police officers are distressed. It’s not what they come to work to do.”

Ambulance crews were called to the scene, but the man could not be revived. The woman, aged in her 40s, was airlifted to the Royal Melbourne Hospital with serious injuries and remains in a critical condition on Thursday morning.

State coroner John Cain attended the scene on Wednesday night.

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

Barrett, who also attended the scene on Wednesday night, reviewed the body camera footage from the two male officers and described their actions as “brave and courageous.”

He said if police had not intervened, the woman may have been killed by her brother.

“Our hearts go out to the family. You can imagine what the mother’s going through at this moment.

“It’s tragic circumstances for the family and for a relatively small rural community, who know their community and know their police.”

The coroner will investigate.

Barrett said the entire incident unfolded over about four minutes, and the man who died was known to police due to his medical condition.

“Our officers will be getting full welfare support, and we will wrap around them to make sure we can offer them any services we can to help them work their way through this,” he said.

“Our priority at the moment with those two members is their mental wellbeing. Making sure they’ve got mental support, making sure their families have got mental support, and that they are well cared for.”

Homicide Squad detectives will investigate the matter with oversight from Professional Standards Command, which is standard procedure for a fatal police shooting.

Two police officers are receiving support after the shooting.

Police appealed for anyone who witnessed the incident or who could provide further information to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au

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