The NSW central western local government area of Dubbo will go into a one week lockdown, while the Hunter area looks set to stay under restrictions.
Premier Gladys Berejiklian said the lockdown would begin at 1pm on Wednesday after a Dubbo woman in her 40s and a young child from the same household tested positive to COVID-19.
"I understand community leaders have already been advised of that. It will occur from 1pm today," Ms Berejiklian announced on Wednesday.
About 38,000 people living in Dubbo and surrounds were already on high alert after authorities found fragments of the virus in Dubbo and nearby Mudgee at the weekend, and Dubbo West Public School was closed on Wednesday after a case there.
The premier also foreshadowed the Hunter New England region, which had 14 cases overnight, would stay in lockdown.
"The Hunter doesn't look like it will come out of lockdown later this week, however we will wait on health advice," she said.
There were more "positive signs" for Armidale, Tamworth and the Northern Rivers, where no new cases were recorded.
NSW Chief Medical Officer Kerry Chant said the source of the Dubbo cases was being investigated.
"The community has been responding to testing but we need to redouble efforts so we can identify the source," she said.
NSW recorded 344 cases on Wednesday with 101 infectious in the community for part or all of their infectious period.
Dr Chant was scathing about reports people who were travelling from Sydney to the regions to be vaccinated.
"I am appalled that people would think, at this point in time, that is OK," she said.
"Also, it is taking vaccines away from people in Albury, which I don't agree with. There is plenty of access to vaccine in Sydney.
"I don't see that is a reasonable reason to travel many hours for that."
A case had been recorded in Shellharbour in the state's south - a person who travelled to Sydney for work.
NSW Health said the new cases included two people from the Central Coast and one from Northern NSW.
Police Deputy Commissioner Gary Worboys said investigations continued into the case of the COVID positive man and his infected children who travelled from Sydney to Byron Bay in the state's north, prompting the lock down there.
"There's a whole range of things that police can investigate to see whether that journey was bona fide in terms of its reasonableness, in terms of the orders. That will form part of the investigation for sure," he said.
Police were issuing $1000 fines to people caught travelling contrary to health orders.
"We've seen people in these country communities devastated by people travelling from Greater Sydney out into the regional and rural areas," he said.
