Greater Katherine's lockdown has been extended as nine indigenous people in the Northern Territory have tested positive for Covid-19.
The lockdown — which began on Monday following two positive cases — will now end at 6pm (local time) on Monday, November 22.
Deputy chief health officer Dr Charles Pain said it was a "very serious" situation, urging community members to come forward and get tested.
"We have 11 cases now associated with this second cluster. Nine of those, we’re informed, notified to us overnight," he said.
"There is clearly a significant spread in two households. We can see how fast it can spread. We don’t know how far it is spread."
NT chief minister Michael Gunner said cases had also been detected in Robinson River.
"Our rapid assessment team arrived last night and are hard at work," he said on Tuesday.
"Their top two priorities: to offer the vaccine to anyone who needs it and test for new Covid cases."
Senator Malarndirri McCarthy revealed her unvaccinated sister carried the virus into Robinson River.
"I'd like to say a personal message and that is that to my sister, who is the source of the Covid infection in Robinson River, our thoughts and prayers are with her and our family," Ms McCarthy told reporters.
'Desperate fight' for Northern Territory
Mr Pain said they didn't believe the transmission was widespread in Katherine.
“However we cannot be absolutely confident of that. With the testing, although it has not been desirable, we wouldn’t have had the testing rates we would have liked," he said.
“Even with those tests we would have expected to pick up cases if it was widespread, but I don't want to give any false reassurance about that.
“We are in a desperate fight now to identify new cases in Katherine and I do need people to come forward and get tested.”
Mr Gunner said more lockdowns and lockouts were possible.
About 350 people live in the community, with 77 per cent fully vaccinated and 87 per cent have had their first dose, according to NT Health.
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