The true impact of the Sydney lockdown protest won’t be known for days, with one medical expert warning the thousands of people who attended could plunge all of NSW into lockdown.

Greater Sydney is already preparing for another lockdown extension announcement this week, with editor of the Medical Journal of Australia, Professor Nick Talley, saying there is a high chance demonstrators who travelled to the protest from outside Sydney could spread the virus into regional areas of the state.

Thousands descend on Sydney’s Town Hall for anti-lockdown protest. (Photo / NCA)

 “This was an idiotic thing to do, just idiotic. Yes, we risk a superspreader event,” he told 2GB on Monday morning.

“There were people from, not only across Greater Sydney, but I understand people from also outside of Greater Sydney at those protests.

“That means we might even risk outbreaks outside of Greater Sydney that really lead to the whole state locking down. Just a disaster.”

Thousands of people converged on the Sydney CBD on Saturday to protest the lockdown, with images and videos showing unmasked demonstrators packed tightly together shouting “freedom” and holding anti-lockdown and anti-vaccination signs.

The demonstration quickly descended into chaos, with protesters reacting violently towards police officers and attacking police horses.

So far 63 people have been arrested in relation to the protest and at least 90 were issued fines for breaking public health orders.

NSW Police say they have received more than 5500 reports from members of the public regarding the protest.

Premier Gladys Berejiklian said she was “absolutely disgusted and disappointed” in those who attended the protest, warning it could lead to a “super-spreading” event.

“We don’t want a setback, and yesterday could have been a setback. Time will tell,” she said on Sunday.

“But I’m just so utterly disgusted, disappointed and heartbroken that people don’t consider the safety and wellbeing of their fellow citizens.”

Police Deputy Commissioner Gary Worboys described the events that occurred on Saturday as “violent, filthy, risky behaviour”.

He said a strike force had been set up to investigate the protest and urged anyone with video footage, photos or any information to submit it to Crime Stoppers.

“The investigation into people’s behaviour yesterday will continue for some time, so I expect over the next few days and perhaps weeks that number of penalty infringement notices will continue to be high,” Mr Worboys said.

Men wearing Anonymous masks during the protest in Sydney. (Photo /NCA)

It comes as the NSW government has requested financial modelling for an extension of the Greater Sydney lockdown until mid-September.

The state’s crisis cabinet will convene this morning to discuss a significant lockdown extension, according to The Australian.

The publication reports a September 3 lockdown end date was originally considered but officials are now understood to be modelling multiple financial scenarios, including one where stay at home orders remain in place until September 17.

Speaking to 2GB, Professor Talley said he wouldn’t be surprised if the lockdown remains in place into September.

“NSW is in a terrible place and it’s really sad that this is where we are now. I think it will be extended and how long – it’s unclear,” he said.

When asked why NSW has struggled to get this outbreak under control, Professor Talley said it was a combination of the highly-infectious nature of the Delta variant, not locking down early enough and not having enough people vaccinated.

“I think we needed to squash it very hard very early if we were going to succeed fast enough and that just didn’t happen. And of course we are largely unvaccinated which is also a problem and I think that’s why we are where we are,” he said.

“We just have to deal with where we are now rather than worry about the past.”