At least four people have been killed in a shooting in Darwin when a gunman set off up to 20 rounds of a pump action shot gun.
A 45-year-old man was arrested after being on the run for around an hour following the shootings in and around a hotel in Darwin's CBD.
The incident started with reports of a man firing a sawn-off pump action shotgun at the Palms Motel in Woolner at about 5.50pm on Tuesday.
There are reports of multiple shooting scenes.
One witness in the Pioneer Hotel across the road from the Palms initially believed he heard a fire cracker.
"We were sitting in the front here having a couple of quiet drinks and the first few shots were 'is it a fire cracker?' Then I realised no it's not. It was very high pitched, a gun," he told the ABC.
"I would probably say that 15 to 20 rounds went off over the next five minutes and when we were sitting at the front here, it got very confusing so everybody was taken inside."
Another witness said he took one victim out of the motel.
"Me and this older gentlemen, we watched him walk from room to room shooting every room and we couldn't go in there because it was a crime scene," he told the ABC.
"We got one person out, this gentleman over here but we didn't realise there was another person in there."
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.
Police earlier said the suspect was described as wearing a high-vis shirt and driving a white dual-cab ute.
It is not believed the incident is terror-related, police say.
"There is no known ongoing threat to the community however a police operation remains underway," Northern Territory Police, Fire and Emergency Services said in a statement on Facebook just before 9pm.
"Police can confirm that there is currently four casualties, multiple injuries and multiple crime scenes."
Speaking in London, Prime Minister Scott Morrison said the shooting was a "terrible act of violence".
"I just want to extend my deep condolences and sympathies to all the people in the Territory and particularly in Darwin," Mr Morrison said.
"This is a very tight community and I know they will be rocked by these events."
