There have been four confirmed COVID-19 cases in Tennant Creek, with the town put into immediate lockdown, Acting Chief Minister Nicole Manison has said.

Ms Manison told a press conference Thursday afternoon there were eight new confirmed cases in the NT, six linked to the so-called Katherine cluster.

She said said four of those were from Tennant Creek, with an unvaccinated 40-year-old woman with links to the Katherine cluster getting tested at Tennant Creek Hospital yesterday, with a positive result confirmed today.

Authorities believe the woman has been infectious in the Tennant Creek community since about Sunday, and had been in the Wuppa town camp.

Ms Manison said there were three other confirmed positive cases in Tennant Creek: a woman in her 40s, a woman in her 30s, and a child.

She did not talk about any connection between the four people, and no journalist asked about any connections.

She said the vaccination rate in the town was 83 per cent first dose, and 70 per cent double dose, but did not say if they were NT Government or Commonwealth figures.

The Barkly had the lowest vaccination rate in the NT, and Tennant Creek had already gone into lockdown, which would remain in forced until Monday at 5pm, she said.

A CHO direction was also issued that anyone who has left Tennant Creek since December 10 must isolate, and remain isolated until they get a negative COVID-19 PCR test result.

There is also a mask mandate for the whole of the Barkly local government area, until 5pm on Monday.

People are allowed to drive through Tennant Creek and stop for fuel, Ms Manison said.

Ms Manison said two people from Katherine East, a woman in her 30s, and a teenage boy, who were in Howard Springs quarantine also tested positive, but are considered low risk to spread the virus to the community.

There were also two double vaccinated men in their 20s who flew from Brisbane to Yulara on the Jetstar flight JQ-667 she said.

The men were informed they were close contacts while in transit and received a positive point-of-care test in Yulara, which was later confirmed in a PCR test, Ms Manison said.

On Wednesday, there were 11 new confirmed cases announced – four linked to the Katherine outbreak – including a mother in her 30s, and her 10-year-old son who caught the bus from Timber Creek to Darwin via Katherine, on their way for surgery in Royal Darwin Hospital, and tested positive on arrival.

Despite this potential exposure there was no press conference on Thursday, which attracted the attention of the Opposition with deputy leader Gerard Maley said either Michael Gunner, Nicole Manison or Natasha Fyles needed to explain the movements of a woman and her baby who were positive with COVID-19 after arriving in Darwin from Timber Creek via Katherine that has become a “serious concern” for the public, but were unable to do that because they want to hide from ongoing individual scandals.

For more information on COVID-19 and the lockdown visit the NT Health coronavirus website.