
Quinn Patterson bought firearms on TradeMe and was selling accessories for military weapons right up to the day of his death.
The online auction site confirmed the trades - made by the man who shot and killed two women at his Northland property, before he later died at the scene - last night after inquiries by the Herald on Sunday linked him to a TradeMe account offering police tactical or military-style weapon accessories.
The revelation adds to mounting pressure on police to reveal what they knew - and whether there were warning signs they should have spotted.
Investigating officers are refusing to answer a series of questions about their dealings with Patterson - even as the Police Association yesterday suggested "alarm bells" should have gone off.
Neighbours have told the Herald on Sunday of an arsenal of weapons Patterson had accumulated - including "semi-automatic" guns - and that a former police officer who lived in the area told residents to "be wary" of the man prior to the shooting.
Friends of Patterson have said his armoury included rifles, shotguns, handguns and grenades.
And yesterday it also emerged that police had visited Patterson's home last month after receiving information about the construction of a "small, possibly illegal structure" that had been built.
An officer visited the property, was told it was used for target practice, and left satisfied it was a "tenancy matter that required no further action".
On Wednesday, Patterson shot dead property manager Wendy Campbell and her daughter Natanya when they went to the Northland rental home with contractor Jeff Pipe to carry out repairs. Pipe was wounded but escaped, and is now at home recovering. Yesterday, detectives were at Pipe's waterfront home.
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