"Our thoughts are with the family at this difficult time."
As the matter has now been referred to the Coroner police said they were unable to comment further.
Police confirmed a 50-year-old woman was the only other person injured in the incident.
She remained in a serious but stable condition in Dunedin Hospital following the shooting around 6.30 last night.
Social media linked the pair as mother and son but police have not confirmed that, saying only that they were related.
Several vehicles arrived and left the Otatara address during the morning. They appeared to be private vehicles rather than unmarked police cars.
On Tuesday evening police set up cordons in the rural Invercargill suburb saying they were searching for Johnston.
Police said in a statement they were not looking for anyone else in relation to the shooting.
The injured woman was taken to Southland Hospital before being flown by helicopter to
Dunedin Hospital.
Initial reports said the woman was shot outside the Otatara Four Square store, on Dunns Rd, but the owner, who did not want to be named, said this morning that was not true.
The incident had happened somewhere on Dunns Rd but he did not know where.
The man's body was found at 129b Otatara Rd, one of four houses accessed from a private driveway. It is about 1.5km from the store.
A neighbour said he knew the dead man as Kevin but did not know anything about a woman living at or visiting the property.
Kevin operated a property maintenance company and owned his home, the neighbour said.
He had lived there for about a year.
The neighbour, who did not want to give his name, said he saw Kevin running down the
driveway from 129b about 12.15pm on Tuesday.
He continued to run along Otatara Rd towards Dunns Rd.
"He dropped his socks just by the gate, and then took his shirt off. He ran off wearing three quarter pants and nothing else.... He was out of control.''
The neighbours said he saw the man again, about 1pm, about 6km away at the Stead St reserve on the outskirts of Invercargill.
Later in the evening he read about the shooting on Facebook and telephoned the police to tell them what he had seen earlier in the day.
He said he never heard any arguments or gunshots during the day or evening.
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