Anti-lockdown protesters who gathered at Wollongong's Flagstaff Hill on Saturday were "totally irresponsible", said the city's Lord Mayor.
Up to 400 people - most of whom were not wearing masks - took part in the protest which also including a massed walk along the bike path at North Wollongong.
It was part of a broader series of so-called "freedom rallies", with protests also planned for Sydney and elsewhere for noon on Saturday.
Half of the Endeavour Drive loop was closed by police, who had cars stationed at either end of the closure.
The gates were closed by Wollongong City Council earlier in the week at the request of police to support compliance with the current Public Health Order
The posters and social media posts promoting the event include the phrases "say no to mandatory vaccinations, tyrannical lockdowns and vaccine passports".
At this stage it is unknown whether people have been arrested or penalty notices have been issued.
Wollongong Lord Mayor Gordon Bradbery was concerned this protest would undo all the work the city has done in containing the virus.
"Relatively speaking, we've done very well in comparison to other areas in Sydney but this puts all the hard work and the discipline of our residents at risk," Cr Bradbery said.
"I just think this is totally irresponsible. It's just trying to undo all the hard work and effort that everyone's put in over the past weeks in terms of really being disciplined about the interactions.
"I'm concerned about the fact that this variant of the virus getting into the community, if it gets out of control we will overwhelm the medical system."
He said the protesters' concerns did not match the evidence.
"The evidence is that the present variant is affecting younger people," he said.
"While we're in the midst of trying to roll out the vaccinations we all have to play our part. I know it's challenging but this sort of protest is ill-considered."
Keira MP and Labor's health spokesman Ryan Park said he was "appalled" at the "so called protest gathering" that took place in Wollongong.
"These individuals displayed appalling judgement to think in the middle of a health and economic crisis that it would be acceptable to gather in such large numbers," he said.
"Their decision to protest in this way was an act of complete and utter stupidity and I along with I'm sure many other local residents condemn this reckless behaviour.
"Our community has been hit so hard by this virus. We have thousands of people out of work, we have locals who have lost businesses and we have families who have had to deal with the health impacts of this terrible virus.
"I can only imagine how angry and upset locals who have had to shut their businesses doors and haven't worked for weeks would be feeling as they witnessed these scenes.
"These morons have no consideration for anyone else in our local community especially the police who had to attend the gathering and the health workers on the frontline fighting this deadly virus."
Mr Park said he backed local police in whatever action they took against the individuals who deliberately flouted the current public health orders.
Similar protests took place in Sydney, where "a number" of people were arrested, police said.
"The NSW Police Force recognises and supports the rights of individuals and groups to exercise their rights of free speech and peaceful assembly, however, today's protest is in breach of the current COVID-19 Public Health Orders," a police spokesman said.
The region reported one new COVID case in the 24 hours to 8pm on Friday as the state recorded 163 fresh locally acquired cases.
The new case is a resident of the Wollongong LGA and is in home isolation outside the area.
There are four cases in the Wollongong LGA who are all in home isolation and no local COVID-19 cases are currently hospitalised.
NSW Health also issued an alert for shoppers at Woolworths Wollongong on Friday night.
People who visited the Burelli Street store on Monday July 19 between 4.30pm and 6pm is considered a casual contact who must immediately get tested and isolate until a negative result is received.
"If your date of exposure at this venue occurred in the past four days, you must get another test on day five from the date of exposure," a NSW Health spokesperson said.
The same orders have been issued for anyone who visited the Tahmoor Woolworths on Tuesday July 20 between noon and 12.30pm and the Tahmoor Subway outlet in the Tahmoor town centre on that day between 12.10 and 12.25pm.
The Station Coffee House at Mittagong is also an area of concern for those who visited on July 21 between 6.30am and 8am.
Residents of a North Wollongong apartment block are advised to monitor for COVID-like symptoms.
The residents of the Aura complex in Flinders Street received the notification from the Illawarra Shoalhaven Local Health District on Friday.
"A person who was at the complex has recently been confirmed as having coronavirus infection," the notification stated.
It advises that people who were at the apartment block any time between July 19 to the present "to monitor for symptoms for 14 days (until August 7). If symptoms occur, get tested immediately and self-isolate until a negative result is received".
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