"I can confirm it is a prohibited firearm under the Firearms Act, and we believe that that firearm may have been stolen as far back as 1997," Northern Territory police commissioner Reece Kershaw said on Wednesday morning. "We've got the serial number and we know it's a pump action 12-gauge shotgun."



The alleged shooter has been arrested and identified as Ben Hoffman, 45, who Kershaw confirmed was on parole and wearing an electronic monitoring bracelet at the time of the shooting.

University of Sydney associate professor Philip Alpers is the director of GunPolicy.org, an online gun legislation research tool. He says what happened in Darwin was the biggest non-domestic shooting in Australia since the 1996 Port Arthur massacre, which left 35 people dead.

“[The Darwin shooting] shows that Australia still has a way to go in confiscating and destroying all of these weapons,” Alpers, who works at the university’s school of public health, told BuzzFeed News.

Alpers, who has been researching gun policy for 27 years, said the type of gun allegedly used by the Darwin shooter "should have been surrendered and destroyed" in the gun buyback program prompted by the Port Arthur massacre.



"Pump action shotguns were one of the firearm types which were deliberately targeted by the John Howard government because they were the choice of mass shooters," he said. "They were the weapons of choice in mass killings… that is why Australia prohibited them."



After the Port Arthur killings, Australia banned assault rifles and some semiautomatic rifles and shotguns, and tightened restrictions on gun purchases.

“Both the Australian public and the Australian police in particular have had a considerable attitudinal shift since Port Arthur and the massacres which preceded it, because remember we had a string of about 14 massacres and Port Arthur was just the last straw,” Alpers said.



Unlike in the United States, police in Australia have a broad mandate when it comes to confiscating and destroying weapons they believe are a "danger to the community".

"[Australian police] have always had the right under law to enter any premises where they suspect firearms are being kept or stored illegally and to search those premises," he said. "They have always had the right to confiscate, especially in cases of heightened risk such as apprehended domestic violence."