At least four people have been killed and others are injured after a Darwin man allegedly went on a shooting rampage across the city.

Four men have been killed and a woman has been rushed to hospital with gunshot wounds to her legs after a Darwin man allegedly went on a shooting rampage across the city last night.

Parts of the city were thrown into lockdown just after 5.45pm as police scoured the city to find the alleged gunman, armed with a sawn-off shotgun.

One witness, Matt James, who was at a nearby hotel at the time, said there were “surreal scenes” as alleged gunman “fired upon everyone”.

“He was allegedly walking around screaming out for ‘Alex’,” he told the Today show this morning.

“It just seems so insane.”

Speaking at a press conference last night, NT Police Commissioner Reece Kershaw said the alleged gunman, who can now be named as Darwin man Ben Hoffman, had been out on parole after being freed from jail in January.

Mr Kershaw said Mr Hoffman was well-known to police and was wearing an electronic monitoring bracelet as he evaded officers through Darwin.

After being on the run for more than an hour, the 45-year-old called the NT Police Duty Superintendent and asked to be placed in protective custody, Mr Kershaw confirmed.

“We do believe he was trying to hand himself in,” Mr Kershaw said.

The NT Police Commissioner confirmed the suspect, described as caucasian and wearing high-vis workwear, had been in jail for more than a year before he was released on parole in January.

Police are also investigating the man’s alleged links to local outlaw motorcycle gangs.

“Unfortunately and sadly four people have lost their lives,” Mr Kershaw said.

Around 100 police were placed around the city to ensure public safety. Now, the suspect is in custody in hospital.

CCTV captures moment gunshots fired in Darwin shooting (Today) See the moment an alleged gunman sped off after firing a number of shots in Darwin. Courtesy: Today

Last night, NT Police Duty Superintendent Lee Morgan told news.com.au police were still working to confirm the exact number of injuries and deaths due to crime scenes being scattered across the city.

“We’re still working through a number of crime scenes so we still don’t know if there are others,” he said.

HOW IT HAPPENED — WHAT WE KNOW SO FAR

5.45PM: FIRST SHOTS FIRED

The first calls to police came after shots were heard on Finniss St in central Darwin.

Witnesses reported hearing up to 20 shots fired at the motel, telling horrifying stories of the man allegedly calmly walking through the motel “looking for somebody”.

“He shot up all the rooms and he went to every room looking for somebody and he shot them all up, then we saw him rush out, jump into his Toyota pick-up, and rush off,” witness John Rose told the ABC.

The man then jumped in his ute and drove a block away to the Palms Motel on McMinn St where he allegedly killed one person. The shooter was described as a caucasian man, wearing hi-vis workwear, who’d emerged from behind the motel with a high-powered shotgun.

Later, a man’s body is discovered at the hotel between Finnis and McMinn Street.

5.54PM: GARDEN HILLS CRESCENT

The man then allegedly fled the motel scene down to an apartment complex on Garden Hills Crescent in The Gardens, where another person is believed to have been killed.

“We’re still putting together the chronology of events,” Mr Kershaw said.

A witness told the ABC police initially drove straight past the man.

“We looked through the window and there was a guy with a gun. We put (our car) in reverse and went straight back. As we were going around the block, we saw him walking calmly through the unit blocks. The cops came around, went straight past him because they didn’t know who he was, he was that calm,” the Darwin local said.

“For Darwin, it’s beyond belief. I couldn’t even believe what I was witnessing at the time let alone now it just seems so insane." Darwin local Matt Hames was at a nearby hotel when the terrifying shooting took place. #9Today pic.twitter.com/PgGMFer3KW — The Today Show (@TheTodayShow) June 4, 2019

“He put his gun in the boot (of his ute) then reversed out. The cops followed him and they took off down the street and then we just heard gunshots again.”

5.59PM: THE BUFF CLUB

It’s understood the other man was killed at The Buff Club in Stuart Park. The social club and bar remained open last night, according to NT News.

6.05PM: JOLLY STREET

The man is also alleged to have broken into a home at Jolly Street in the small suburb of Woolner, where he shot and killed another man. It’s alleged he had a shotgun in his hand at the time.

6.22PM: PETER MACAULEY CENTRE, BERRIMAH

Police said the man attended NT Police Headquarters, called the Peter Macauley Centre in the outer Darwin suburb of Berrimah before he was arrested.

6:44PM: ARREST

After being on the run for more than an hour, the man was tackled on Stuart Highway at the Daly Street Bridge, by heavily-armed tactical response group police dressed in camouflage gear.

Before his arrest, he’d spoken to the Duty Superintendent Lee Morgan from Darwin police, according to NT News. He’d requested to be taken into protective custody.

Video taken at the scene shows the man, covered in blood and shirtless, lying on his back as he tried to kick the rifle of one of the police officers.

The man was tasered at the scene before being taken away in a police vehicle. He was subjected to mandatory drug, alcohol and other testing.

Dramatic arrest if possible shooter in Darwin CBD pic.twitter.com/0fis1UQHW9 — Stephanie Zillman (@Steph_Zillman) June 4, 2019

Police said there were at least five different crime scenes they would spend the night working through.

The main crime scene is The Palms Motel on McMinn St in Darwin. Officers have also cordoned off Garden Hills Cres, a Coles Express petrol station on Daly St, Jolly St in Woolner, The Buff Club in Stuart Park and finally the roundabout where the 45-year-old was arrested.

Another crime scene has been declared at the Peter McAulay Centre — the central complex for policing in Darwin — after the man allegedly tried to gain entry to the building.

Mr Kershaw said police had received reports the man had allegedly fought with someone at the Buff Club, ending in a knife and gun being drawn.

“Our investigation will be evidence-based and intelligence-informed,” Mr Kershaw said.

Mr Kershaw praised the actions of police — who managed to have the alleged gunman in the back of a paddy wagon within the hour.

“This was a first class response. Within the hour, we were able to apprehend and take that offender safely into custody,” he said.

Mr Kershaw said the man allegedly still had his shotgun when the tactical response group arrested him.

Mr Morgan said police believe the shooter acted alone. He was driving a white Toyota Hilux ute and was described as 195cm tall.

NT Chief Minister Michael Gunner told reporters: “This is not the Darwin we know”.

“I understand when an event like this occurs, people’s fears turn to terrorism. I can confirm we do not believe this is not a terrorism incident,” he said.

“This many be an event you prepare for but this is never an event you want to respond to. It is an incredibly difficult night. Territorians can be proud of those who serve us on our front line.”

Witness Leah Potter told the ABC she helped an injured woman after the alleged shooter fired his shotgun through a motel room door.

Ms Potter told the publication she heard something that sounded like fireworks near the Palms Motel in Darwin before seeing the woman carried outside.

Her legs were bleeding and peppered with shotgun pellets.

A man, believed to be the injured woman’s boyfriend, dropped her on the road to go and get help from police.

“A man came running with a woman in his arms from next door which is the Palms Motel, which is the motel next to my motel, and he just dropped her on the footpath right in front of us,” Ms Potter said.

“I ran and got some towels and wrapped up her legs, she had little holes all in her skin on both her legs and she was bleeding everywhere.”

Large sections of the city were closed down earlier yesterday as police worked to find the man.

Police armed with assault rifles and wearing camouflage gear cordoned off roundabouts and roads in Darwin.

Speaking from The Australia-UK Chamber of Commerce in London, Prime Minister Scott Morrison said his thoughts were with the NT.

“It’s a terrible act of violence that has already taken lives,” Mr Morrison said.

“Particularly, I want to extend my deepest condolences and sympathies to all the people of the Territory and particularly in Darwin. This is a very tight community and I know they will be rocked by these events.

“Our advice is that this is not a terrorist act, nothing to suggest this was the case whatsoever. The true motivations of this criminal and violent act will become better known … but in the meantime I think it is important that everyone in Darwin, in the Territory, understands that the thoughts of Australians, wherever they are, will be thinking very much of their fellow Australians in the Territory.”