Victoria has recorded 428 new coronavirus cases, which is by hundreds the largest COVID day anywhere in Australia.
Premier Daniel Andrews announced a number of 5165 in the state on Friday.
Of the new incidents, 57 are linked to documented outbreaks, one is from hotel quarantine and 370 are being investigated.
There have also been three deaths in the past 24 hours following the passing of a man aged in his 80s, a man in his 70s and a woman in her 80s.
In the past two days, nearly 750 cases of COVID-19 were reported in Victoria, after 317 cases were registered on Thursday.
“I know no one is enjoying being in a six-week lockdown,” Andrews said.
“But at the same time they are the only tool that we have. We do not want to extend this longer than six weeks, we do not want to have to put in additional rules.”
Two men in their 80s also died on Thursday from the virus, and the death toll of the state now exceeds 30.
A total of 122 patients are currently in Victorian hospitals due to the outbreak, which is a 13-fold rise from a previous day.
A positive case was confirmed earlier on Friday at Costco in Epping, and the worker worked between midday and 7 pm last Saturday.
Melbourne and the Mitchell Shire are now in a six-week lockdown for many days, where people are only permitted to leave their homes for food , exercise, work or education and care.