Man killed outside station had no history with police

Two constables confronted the knife-wielding man as he approached the entrance to the station, shooting him twice, he said.

The man was not previously known to police.

"He has no involvement with police whatsoever," Det A/Supt Brosnan said.

Footage from the officers' bodyworn cameras and CCTV captured the fatal incident. (Fraser Barton/AAP PHOTOS)

The officers involved will be interviewed by the Ethical Standards Command as part of an investigation being overseen by the state's Crime and Corruption Commission.

Any interactions with the mental health system, as well as any influence drugs may have had will also be scrutinised.

"That will obviously form part of the investigation to determine exactly what he was doing there and what his motivations were," Det A/Supt Brosnan said.

Footage from the officers' bodyworn cameras and CCTV captured the incident.

Two other officers performed first aid after the man was shot.

The police station is next to an ambulance station, but Det A/Supt Brosnan said he was not in a position to comment about why the man could not be saved.

"I'm not a doctor, but it's a gunshot wound," he said.

The use of lethal force indicated there was a threat of grievous bodily harm or death and he was confident police acted appropriately, he said.

"We would rather have had a better outcome, we would rather have de-escalated the situation.

"Unfortunately at times, we are not given that opportunity and as such have to use lethal force, but it's not something that we do lightly, and it would be something we would rather avoid," Det A/Supt Brosnan said.

The man's family has been offered counselling services, as have the officers, who are so far doing "okay", Det A/Supt Brosnan said.

"The post traumatic stress from this incident may not be felt for some time ... we're doing everything we can to support the officers."

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