A Covid-positive woman who lied on her border form when entering Darwin has been fined while authorities are confident the Top End's three-person cluster is now under control.
Chief Minister Michael Gunner said the 21-year-old was issued with an $5024 infringement notice after she was questioned by Northern Territory detectives for five hours.
"Don't lie, don't be selfish, think of others," he said on Sunday.
"She will pay because she lied to officials."
Mr Gunner said the woman's actions had "put the Territory at risk", prompting the three-day lockdown for Katherine, 320km south of Darwin, where a close contact travelled and tested positive.
'Lockout' expanded despite no new cases
There has also been a "lockout" for Greater Darwin, which Mr Gunner expanded for an extra 24 hours to midnight on Monday, with only vaccinated people permitted to move freely about the community.
Mr Gunner said on Sunday there had been no new cases overnight and the cluster remained at three.
He said he was confident that from 3pm on Sunday the lockdown in Katherine would be scaled back to a lockout and "if all goes well" the town will exit lockout at the same time as Darwin.
Darwin on alert as exposure sites grow
Before arriving in Darwin the woman spent time in Melbourne, where Mr Gunner said she "almost certainly" contracted Covid-19 before spending time in Adelaide and Cairns.
She arrived in Darwin from Queensland on October 29.
"While there were compassionate reasons for her decision to visit Victoria there were not compassionate reasons for lying to the Territory in coming here from a hotspot," Mr Gunner said.
There are now additional exposure sites in Darwin including food and retail outlets.
The woman is a close contact of the index case, an unvaccinated man in his 20s who worked at RAAF Tindal, near the town of Katherine.
They spent last weekend at the Mantra Hotel in Darwin together after she arrived from Cairns.
The man also visited Monsoons pub and nightclub before testing positive for the virus on Thursday.
Mr Gunner said the man had "saved lives" by getting tested as soon as he was symptomatic.
"His next job is to get vaccinated."
Mr Gunner said 119 of 123 close contacts identified in the cluster had been contacted and were isolating.
Protesters charged over 'disgraceful' behaviour
Meanwhile, NT police have charged seven protesters who rallied against mandatory vaccines in Darwin.
They said they were conducting health compliance checks around the city on Saturday when a group of protesters walked toward one of the check points.
"A small number of people refused to engage with police and used violence towards officers," the force said in a statement.
Superintendent Daniel Shean said the behaviour was disgraceful and there would be further investigations to identify additional people.
"Our officers have had chemicals, rocks and punches thrown at them in the course of enforcing the (Chief Health Officer's directions)," he said.
The seven people were charged with offences including aggravated assault, assaulting police, riotous behaviour and breaching health orders.
They were bailed to appear in court at a later date.
As of Saturday 79.9 per cent of the territory's eligible population aged over 16 had received at least one dose of a Covid-19 vaccine while 66.7 per cent were fully inoculated.
Do you have a story tip? Email: email@example.com.