A man shot dead by police in Sydney was allegedly behaving "erratically", "aggressively" and "chasing people down the street".
Residents locked their doors as police responded to a call in North Willoughby about 11.30am today.
Officers were confronted by Steven Pampalian, who was allegedly armed with two chef-style knives.
A constable shot Pampalian and he died at the scene, NSW Police said in a statement.
Assistant Commissioner Leanne McCusker said Pampalian was approaching neighbours and various homes.
"As police arrived, they were confronted by this man," McCusker said.
"At the time he did have two large knives on him.
"He ran at police and one of the police officers then discharged their firearm.
"He is known to police but I would probably describe that as quite minimal and any further detail about this person will form part of the critical investigation."
McCusker said it is unclear what triggered the man's actions or if the incident is mental health related.
The two officers are receiving welfare support.
"Naturally they are shaken but welfare support has been put in place with the view that we look after them," McCusker said.
No other injuries have been reported.
Police are investigating the circumstances of the incident and the investigation will be reviewed by the Professional Standards Command.
McCusker said a Taser was not used during the incident but it was "a tactical option available".
"In terms of the tactical option that was used, that will be subject to the investigation by the critical incident team," she said.
McCusker said she has not reviewed the bodycam footage however she plans to look at it.
One woman told 9News she felt "shocked" and "sad" that someone has died.
"We just heard quite loud shouting and a man quite upset then three loud gunshots," she said.
"Well, I didn't know they were gunshots, just loud bangs and just thought, 'Was that gunshots?'
"Then I'd heard this street had been blocked off and we heard the helicopters.
"We just closed the doors and stayed inside."
Nearby Willoughby Public School was locked down during the incident as a precaution.
The shooting will be investigated by the Homicide Squad.
A report will be prepared for the coroner.
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