Victorian authorities have imposed some of the toughest restrictions in the world on residents living in Melbourne.
As of yesterday, the Australian state has 6706 active cases.
The Australian reporter Rachel Baxendale told Mike Hosking officials haven't been able to find the source for more than 2100 cases.
She says it's a pretty awful situation because there's another 3400 or so cases still under investigation.
Australians in Victoria who break Covid-19 stage four restrictions will face a hefty fine - as officials struggle to bring the virus under control.
Premier Daniel Andrews says there are $5000 spot fines for those who breach the rules, and repeat offenders will end up in court.
He says the maximum penalty is $20,000 dollars.