The Northern Territory has detected four new COVID-19 infections linked to a community outbreak, with another seven cases among travellers.

It comes as authorities tweak the territory’s new rules for travellers from Monday, with more freedom to move about the NT.

The new community cases include a woman in her 20s from Katherine, which has become the epicentre of the outbreak, 320km south of Darwin.

A teenager boy from one of four “high-risk” streets in the town’s east had also tested positive, Acting-Chief Minister Nicole Manison told reporters on Wednesday.

A woman in her 30s and her young son from Timber Creek, 225km east of Kununurra in Western Australia, have also contracted the virus.

The pair were diagnosed in Royal Darwin Hospital after travelling from the remote town for unrelated health treatment.

“There will be exposure sites from these two cases. We know they stayed in Katherine, and they caught a bus to Darwin,” Ms Manison said.

It brings the current outbreak to 94 cases with more expected.

It started when an infected woman illegally entered the NT in late October.

The 21-year-old was fined for lying on her border entry form as the virus spread from Darwin to Katherine and three Aboriginal communities.

Police have since launched a fresh investigation into the border breach after an Aboriginal woman died from COVID-19 in early December.

Meanwhile, five travellers from South Africa have also tested positive at The Centre of National Resilience quarantine facility at Howard Springs after arriving on a recent repatriation flight.

A Qantas aircrew member has been diagnosed with the virus after working on a recent London flight.

A person quarantined at home in Darwin has also contacted COVID-19.

Travellers to the NT from Monday are no longer locked into high-vaccination areas, such as Darwin, for their first 14 days in the territory.

After consultation with outraged members of the tourism industry and parents of boarding school students, recent arrivals can travel across the territory so long as they avoid vulnerable communities where vaccination rate are low.

Under the new rules, all travellers to the NT must be fully vaccinated and have a PCR tests before and after arriving.

Unvaccinated returning residents can enter the NT but they must quarantine for 14 days.

Travellers who live or work in vulnerable communities can enter low-vaccination zones but they must undertake a PCR test before they do.

They must also wear a face mask in public and take daily COVID-19 tests for their first seven days in the community.

A lockout was declared in Timber Creek and the nearby community of Gilwi late on Tuesday.

The town of Kalkarindji, 550km south of Darwin, and nearby Daguragu also entered a lockout at the same time.

It will remain in place until 2pm on Friday.