South Australia's Premier Steven Marshall says coronavirus will be difficult to eradicate in the state if it gets a foothold in the community as he reveals "potentially thousands" of people visited a "site of concern".
Here's a summary of what happened on Thursday:
- South Australia reported no new cases on the first day of its lockdown
- Mandatory weekly COVID-19 testing for hotel quarantine staff was rolled out in Western Australia
- Victoria made it 20 days without recording a single case or coronavirus-related death
- Premier Daniel Andrews announced the Victorian border to South Australia would close for two days from midnight
- NSW said it would ease restrictions for New Year's Eve
