Police at the scene of a shooting outside Warners Bay Post Office on Wednesday afternoon. Credit:Marina Neil Police said the man died at the scene after a police firearm was discharged. In a video that purports to show the man's final moments before he was shot, several police officers appear to have their firearms drawn. Shouts of: "Put it down ... put the knife on the ground" can be heard in the video that appears to have been shot on a smartphone from a car park just metres from the police operation. Police appear to yell "C'mon mate. You don't want to do this ... Put it on the ground or we'll shoot" before three shots ring out.

The scene of the shooting at Warners Bay. Credit:Marina Neil A witness said the victim looked "distressed" in the minutes before he was gunned down. The witness, who did not want to be named, was standing in the car park across from the post office when she saw a man "holding a butcher's knife to what looked like a staff member". A man leans against an Australia Post letterbox at the scene of a shooting outside Warners Bay Post office on Wednesday afternoon. Credit:Marina Neil "The guy who looked like a staff member kept his distance and at one point he had to run away, he didn't turn his back but he had to run to stop him [the attacker] coming towards him," the witness said.

She said she and a friend immediately called the police. The aftermath of a shooting outside Warners Bay Post Office on Wednesday afternoon. Credit:Marina Neil "Two guys came up and tried to stop it. They were telling the guy to put the knife down but he wouldn't. "He looked really distressed. One hand was holding the knife and the other was kind of covering his face. Like he had his head in his hands. But he was wearing sunglasses the whole time." The witness said that police arrived within four minutes.

"Two police officers rocked up and got out. They were holding their guns up and yelling at him to put the knife down but he still wouldn't," she said. "Then he came at the police with the knife. He didn't run, but he came at them, and they just shot him three times," she said. Another witness said she heard shouting and went to the window. "I walked to the window and I saw two men holding what looked to be guns at someone," she said.

"The man was standing holding some type of weapon." She said the entire incident happened in less than a minute. "I called out to my colleagues ... my boss said get away from the window, and we heard three shots. "I came back to the window, there were sirens and police everywhere." An employee at Dawson's Oysters in nearby King Street said she did not see what happened but had been told the man was in the Warners Bay Post Office threatening staff or customers with a knife.

Someone called the police, who arrived within minutes. They confronted the man outside the post office and told him to put the knife down. When he didn't, he was shot. The woman said King Street and the post office street, John Street, were shut off to traffic. A large number of police and police vehicles were at the scene.

Police launched a critical incident investigation into the circumstances surrounding the incident, including the actions of police. That investigation will be overseen by the Professional Standards Command. In a press conference at 6.30pm on Wednesday, Northern Region commander Assistant Commissioner Jeff Loy told reporters that police would be monitoring the welfare of the police involved in the incident. "At this time we acknowledge the grief and suffering of the man's family and also we are looking after the welfare of our police and their families but I can assure you that every aspect of this [matter] will be investigated by a critical investigation team and overseen by the professional standards command," Assistant Commissioner Loy said. While police declined to go into specifics about the incident, they said it would have a major impact on the officers involved and their families as well as the grief-stricken family of the man killed.

"I have seen that footage and that footage will play a significant part in the investigation," he said. "Tonight will be a long night but also a long journey for all the people involved. "[The police involved] are fine at the moment, and we're looking after them. "They have to go through a process of this investigation, and their actions will be accountable, but we'll do everything in our power to make sure their welfare is maintained, and hopefully they'll come through this and we'll move forward. "It does [shake the police involved]. This is why this is such a major event when it does occur."

The union representing postal employees, the CEPU, was working with Australia Post to ensure all those affected by the incident would received appropriate support. "This is an incredibly tragic day," CEPU divisional secretary Greg Rayner said. "Our thoughts are with the family and colleagues of the deceased and also the police officers involved."

