A suspected gunman who opened fire at multiple locations across Darwin was known to authorities and out on parole, Northern Territory Police confirmed.
NT Chief Minister Michael Gunner said four people were dead and another was injured, adding the incident was not terror-related.
“This has been a devastating day in the Northern Territory... This is not the Darwin we know,” he said.
NT Police Commissioner Reece Kershaw said the 45-year-old suspect had been released on parole in January and was wearing an electronic monitoring bracelet.
He said the man was known to police with "a number of interactions, adverse, with the police force”.
Comm Kershaw said the incident started about 5.45pm on Tuesday when an armed man opened fire in Darwin’s CBD area.
Shots had rung out near Finnis Street just outside the CBD before the man moved to other locations – including the Buffalo Club, Gardens Hill Crescent, the Palms Motel, a Coles Express and Jolly Street in Woolner.
“It's appeared he's moved using a vehicle which we have located and seized to those particular sites,” Comm Kershaw said.
The suspect was apprehended about an hour after the shooting spree began by which point four people were dead and at least one person was seriously injured.
NT authorities stated they were still piecing together the sequence of events but emphasised the incident was not terror-related, with the police commissioner telling media the offender’s motives were currently unclear.
“Unfortunately and sadly, four people have lost their lives,” Comm Kershaw said.
“Our hearts and the police family and the wider community are with you tonight (Tuesday) and we're here to support all of our community and those that have lost their loved ones.
“A number of crime scenes have been declared. We have our major crime leading that investigation.
“We also are maintaining an active operation, meaning we have in excess of around 100 police who were involved at both those crime scenes and ensuring that we're maintaining our public safety across the Northern Territory.
Let me be clear. At this stage we do not believe this is terrorism-related. This is one individual who has acted individually and unfortunately taken the action they have.”
The alleged gunman is currently being held in custody at the hospital.
Two people have also been taken to the Royal Darwin Hospital with gunshot wounds and both are in a stable condition, a Northern Territory Health spokeswoman told AAP.
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