The alleged event preceded a dramatic upswing in COVID cases in the region, which has since been couched as an emerging "area of concern" in the COVID pandemic.

According to sources contacted by the Mercury, multiple attendees at the gathering later tested positive to the virus.

Read more: Wollongong, Shellharbour COVID lockdown, as it happens

Lake Illawarra Police are calling on anyone with information about the gathering to come forward.

The Mercury provided police with detailed allegations and received the following response:

"Lake Illawarra Police are aware of ... reports regarding a potential gathering at Berkeley last month.

"Officers are conducting inquiries and anyone with information is encouraged not to post information on social media, but to report it via Crime Stoppers on 1800 333 000 or nsw.crimestoppers.com.au.

"The public health orders are in place for a reason - to protect the community from the spread of COVID-19.

"Police are conducting proactive patrols, compliance checks and traffic operations across major arterial roads and backroads as part of Operation Stay at Home, and are responding to every Crime Stoppers report from the community.

"Accordingly, police will continue to enforce the orders to ensure our regional communities remain protected and as many people as possible are protected from serious illness or even death.

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Questioned about rising COVID-19 case numbers on Monday, NSW deputy premier John Barilaro singled out the Illawarra-Shoalhaven as an area that was "starting to be an area of concern".

He said the region's recent cases were believed "connected to a couple of families and concentrated around that, however there has been exposure in the community and the number of cases continues to rise".

By Wednesday new COVID-19 cases reached a region-wide record of 34, up from 14 new cases on Tuesday.

Of these, 24 residents live in Wollongong, seven in Shellharbour, two in the Shoalhaven and one case is under investigation in Kiama.

Asked about the origins of the Illawarra upswing in cases, Mr Barilaro said: "we have had complex issues around the original [Illawarra] exposures ... trust is important, we are not singling out individuals but if I am able to get any information from the Health District to quash those rumours I will provide it to you".

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