Three additional cases of COVID-19 have been detected in Dubbo overnight, taking the total of active cases in the Western NSW Local Health District to six.
These cases are linked to the cases reported out of Dubbo on Wednesday.
Meanwhile, Newcastle's lockdown will last at least another week, NSW Premier Gladys Berejiklian has confirmed.
Armidale, Tamworth and Northern Rivers had no new cases in Thursday's update.
"Unfortunately the same isn't the case for Hunter and New England," Ms Berejiklian said, citing NSW Health advice.
"Given what the area's experience I think the community would understand why [the lockdown extension] is the case."
Statewide there are 374 cases in hospital. 24 require ventilation, and 62 are in intensive care.
The latest 24-hour case numbers announced Thursday included 345 cases, with at least 60 infectious in the community, and two deaths in NSW.
Ms Berejiklian said the front had moved in Sydney to Cumberland local government area, particularly Auburn and Granville.
Bayside, Strathfield and Burwood local government areas have been added to the areas of concern.
152,000 tests were conducted in a "huge record", Ms Berejiklian said.
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