The Northern Territory has detected three new COVID-19 infections, including an infant who has been taken to hospital.
The new cases are a man in his 40s from Katherine, a woman in her 20s from the Binjari Aboriginal community and a baby boy from Robinson River.
"He's been transferred to Royal Darwin Hospital for care," Chief Minister Michael Gunner told reporters on Tuesday, referring to the infant, who is in a stable condition.
The woman and the man are quarantining in the Centre for National Resilience.
The woman has significant respiratory symptoms.
The infections bring the current outbreak to 40 cases, with wastewater testing indicating there may be many more to come.
Five people are in hospital with two requiring oxygen.
It comes after a man grabbed a needle containing the COVID-19 vaccine from a health worker at a Darwin clinic and jabbed himself before storming off.
"We, unfortunately, had an incident at the Coolalinga vaccination centre," Police Commissioner Jamie Chalker said.
"A gentleman appeared there indicating he was not overly happy with the process.
"He pushed one of the hands away of one of our health staff and grabbed the needle and injected himself with the vaccine."
Health staff are trying to determine whether it can be legally recorded as the man's first dose.
Mr Chalker said the man's wife visited the clinic after the incident and also abused workers.
The Greater Katherine area, about 320km south of Darwin, remains locked down, along with Binjari and the neighbouring community of Rockhole.
It's the second time the Katherine lockdown, which started seven days ago, has been extended, with residents only permitted to leave their homes for the five essential reasons.
Mr Gunner said the town was likely to have some form of lockdown or lockout until December 4.
That may be lifted once it reaches the 80 per cent fully vaccinated rate.
The town's current first dose rate is 83 per cent, with 77 per cent of people fully vaccinated.
The outbreak started when an infected woman illegally entered the NT in late October.
The 21-year-old lied on her border entry form before travelling from Cairns to Darwin after visiting Victoria, where she contracted the virus.
She infected a man in Darwin before the virus spread to Katherine, then the Aboriginal communities of Robinson River and Binjari.
Binjari, 330km south of Darwin, and Rockhole remain under extreme lockdown orders.
The communities' 300 residents are only allowed to leave their homes in an emergency or for medical treatment.
"We've had really good co-operation ... People understand what's happened and why and we've got a lot of welfare teams on the ground as well as health professionals." Mr Gunner said.
"Everyone is getting the best care we can give."
The Australian Defence Force is also assisting.
Vaccination rates in Binjari and Rockhole were reported as being below 70 per cent when the crisis started, with the NT Aboriginal health organisation declining to make the figures public.
All eligible residents in the two communities had now had at least one jab.
All virus tests from Rockhole have also come back negative.
Restrictions have eased at Robinson River, 1000km southeast of Darwin, in recent days, with the lockdown downgraded to a lockout of unvaccinated people.
About 89 per cent of Robinson River's 350 residents have had one vaccine dose and 79 per cent are fully vaccinated.
Australian Associated Press