The Northern Territory has detected three more COVID infections, including a baby who has been taken to hospital.

Tuesday’s new cases were a man in his 40s and a woman in her 20s from the Binjari Aboriginal community and a male infant from Robinson River.

“He’s been transferred to Royal Darwin Hospital for care,” Chief Minister Michael Gunner said.

It brings the current outbreak to 40 cases.

Tuesday’s update came after the lockdown in Katherine, 320 kilometres south of Darwin, was extended until Wednesday at 6pm.

It’s the second time the lockdown that started seven days ago has been extended, with residents permitted to leave their homes only for the five essential reasons.

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 had contracted the virus.

She infected a man in Darwin before the virus spread to Katherine, then the Aboriginal communities of Robinson River and Binjari.

Restrictions have eased in Robinson River, 1000 kilometres south-east of Darwin, where the lockdown is now a lockout of unvaccinated people.

However, Binjari, 330 kilometres south of Darwin, remains under an extreme lockdown order after nine cases were found there on Saturday.

The 190 residents, along with 100 people in neighbouring Rockhole, are allowed to leave their homes only in an emergency or for medical treatment.

Meanwhile, the NT has relaxed some border restrictions for fully vaccinated travellers from red zone areas where the virus is present.

Under sweeping changes to the territory’s border rules, they’re permitted to quarantine at home as long as they follow testing guidelines and return negative results.

A ban on most unvaccinated arrivals has also taken effect, regardless of where they travel from.

The only exception will be essential personnel, those entering on compassionate grounds and Territorians returning from green zone jurisdictions where COVID is not present.

The home quarantine requirement is scheduled to end on December 20, with rapid antigen testing extended to all arrivals.

-AAP