Four men are dead, a woman has been wounded and the alleged gunman responsible is in hospital after an "insane" bloody rampage across five different locations in Darwin.
The 45-year-old suspected gunman, who was on parole, was arrested after being on the run for about an hour following the mass shooting in and around a hotel in Darwin's CBD on Tuesday night.
Detectives will on Wednesday start piecing together the sequence of events, including the motives of the shooter, who's been named as Darwin local Ben Hoffmann.
He was arrested at the busy Stuart Highway and McMinn Street intersection near where the shootings occurred.
Moonman In The Morning spoke with an eye witness this morning:
Television footage showed him on the ground after being dragged from under his white dual cab ute, kicking his legs at officers from the Northern Territory Police Territory Response Group.
The incident started with reports of a man firing shots at Finnis St at about 5.50pm just outside the Darwin CBD, with the four deaths occurring at the nearby Buffalo Club, Gardens Hill Crescent, the Palms Motel and Jolly Street.
He also tried to enter the Peter McCauley Centre police station to possibly hand himself in, then phoned a duty superintendent who did a "magnificent job in negotiating with him" before the arrest, Police Commissioner Reece Kershaw told reporters.
A group of about a dozen men who were friends and relatives of a man who died at the Palms Hotel gathered outside after the shooting and many were in tears.
Darwin local Matthew James was standing in a carpark nears the Palms when it all began.
"It was just surreal," he told Nine's Today program on Wednesday. "All of a sudden there were these gunshots."
"Moments later someone came running towards me carrying this woman who was covered in blood and just basically put her at my feet and she was screaming that she had been shot.
"The guy that actually carried her up was pretty frantic at the time, saying he had opened the door and there was a gunman there with a shotgun and he proceeded to fire upon anybody inside the building."
Mr James told AAP the woman was hysterical.
"She was caught up in it, she said 'I've been shot, I don't know why, I don't have anything to do with anything', he said.
The woman told Mr James the shooter had been going from room to room, firing his gun and shouting the name of a man - Alex.
"It just seems so insane," Mr James said.
Known to his friends as "Hoffy", the actions of the alleged shooter have shocked the Darwin community.
"F********ck... Hoffy,W.T.F...," one person posted on Facebook.
Chris Dalgleish, who was having a beer on the balcony of the Frontier Hotel pub across the road from the Palms, said people raced inside when they realised someone was shooting.
"Everyone started jumping inside, then locking doors and windows and went to the back corner," he told AAP.
The alleged shooter is an outlaw motorcycle gang member, well known to police with a criminal history, and the incident is not believed to be terror-related, according to police.
He was released from prison on parole in January after serving at least a year and was wearing an electronic monitoring bracelet, Mr Kershaw said.
"He is an individual who is well known to police and has a number of interactions - adverse - with the police force," he said.
"We're still trying to establish the intent and the motivation behind this but all I can say is that, sadly, people have lost their lives this evening."
The alleged shooter is in hospital, under guard.
The woman who was injured is also in hospital, in a stable condition.
Speaking in London, Prime Minister Scott Morrison said the shooting was a "terrible act of violence".
NT Chief Minister Michael Gunner said "this was not the Darwin we know".