NSW has reported 163 new locally acquired cases of COVID-19 and at least 45 of those people were circulating in the community for all or part of their infectious period, the state's health minister says.
A man in his 80s from southwest Sydney has also died after contracting the virus.
Greater Sydney and surrounding regions are in lockdown until at least July 30, while three local government areas in regional NSW are in lockdown until at least at least July 28, as health authorities battle to contain a outbreak of the virulent Delta strain.
"Very worryingly, very worryingly, 45 (new cases) were infectious out in the community," Health Minister Brad Hazzard told reporters.
"In other words, 45 people were out walking around and potentially spreading the virus which certainly explains why our numbers are going up."
Mr Hazzard said cases rises were mainly in the southwest Sydney areas of Canterbury-Bankstown, Cumberland and Liverpool.
He said regrettably additional restrictions had to be placed on Cumberland and Blacktown on Friday night to prevent anyone but authorised workers from leaving those local government areas.
"We really need our community, particularly in southwestern and western Sydney, to stay at home, to hear the message and stay at home," the health minister said.
"And don't intermingle with family members from other households. It will continue to cause massive grief here in Sydney, particularly in western and southwestern Sydney, if family members mix with family members from other households.
"Just, please, stop doing it. Stop."
NSW Health issued alerts for another 46 potential exposure sites across Greater Sydney and a number in the Southern Highlands towns of Tahmoor and Mittagong on Friday night.
Sewage testing in Moss Vale has also returned positive results for COVID-19 leading authorities to urge people to isolate and get tested if they develop symptoms.
"There are no known cases in this area, which is of great concern," NSW Health said in a statement on Friday night.
"Everyone in the Moss Vale area is asked to be especially vigilant for any symptoms that could signal Covid, and if they appear, to immediately be tested and isolate until a negative test result is received. If symptoms appear again, please be tested and isolate again."
Australian Associated Press