Alice Springs has become the latest city to be thrust into lockdown after a miner who tested positive for Covid-19 spent several hours in the airport there.
The worker left Newmont's Granites Mine on Friday and spent seven hours at Alice Springs airport before flying to South Australia.
In announcing the decision to extend the NT's lockdown restrictions to Alice Springs, chief minister Michael Gunner said: "Like all our other decision we will not take a punt on this.
"We will operate on the assumption that he has Covid-19, and we will operate on the assumption he was infectious while in the Territory."
The lockdown will last for 72 hours from 1pm on Wednesday.
The direction applies to everyone inside the Alice Springs town council boundary, including hundreds of vulnerable Indigenous Australians who live in town camps.
"We are still in a dangerous period, The territory is still under threat," Mr Gunner said.
Alice Springs joins cities in NSW, Queensland, West Australia and the Darwin area in lockdown.
More than 12 million Australians are in lockdown conditions, while millions more around the country are facing looser restrictions and mask mandates.
South Australia avoids lockdown despite new cases
Adelaide has recorded five new Covid-19 cases linked to a miner who returned from the Northern Territory and tested positive.
Despite speculation in the media on Wednesday morning, the state is not going into lockdown, premier Steven Marshall told reporters.
"While this is a very concerning turn of events, we are very relieved this person and this family have been at home since Saturday," Mr Marshall said.
The cases are not considered to be locally acquired and authorites are optimistic spread has not occurred in the community.
The family has been transferred to Adelaide's dedicated facility for positive coronavirus cases.
The other 28 miners who returned from the same NT mine have also been in isolation since arriving in South Australia.
South Australia is restricting home visits to a maximum of 10 people and urging people to wear masks in public.
Western Australia also recorded a new case of coronavirus on Wednesday.
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