Warren, who was in his 60s, was shot in the driveway of his home in Freyberg Ave on Thursday after he allegedly "held and presented" a firearm at police.
He was given medical treatment by officers at the scene and flown to Dunedin Hospital, where he died early on Friday morning. He had no history with police.
He was unlikely to be formally identified until later this week, she said.
Oamaru Sports and Outdoors co-owner Richard Hill knew Warren, who worked at the store when it was known as Wilsons Sports Centre, for several years.
Warren was a keen angler who advised many of the store's customers about the sport, Hill said. He was also an "outstanding and well-respected staff member" whose services as a fishing guide were in high demand.
"He was a man that was respected worldwide for the fishing guiding that he did. He was a professional guide and was outstanding at what he did. He had a heart of gold. He would do anything for anyone."
Warren also worked at Kurow's Caltex service station.
The service station's owner, who did not want to be named, said he had known Warren for "quite a long time".
"He has not only been an employee, he has been a family friend. It will affect the town for sure. It will rock the town."
One of Warren's neighbours, who did not want to be named, described him as a "quiet and very nice guy".
Warren had lived on the street for about a year, he said.
There would be a critical event investigation into the fatal shooting, the Independent Police Conduct Authority had been informed and were also investigating, and the death would be referred to the Coroner.
