Victoria's Covid-19 cases have surged again, with the state recording 11 new locally acquired infections.
The additional cases were confirmed by the Department of Health on Thursday morning and takes the number of known community cases to 26.
There were officially 12 local cases announced, however one of the cases was identified on Wednesday.
It is unclear at this stage how many of the new cases are linked to the previous 15 cases.
Acting Premier James Merlino will face media later on Thursday and is expected to announce a snap lockdown for Greater Melbourne and potentially for the entire state, the ABC reported.
The state government and health authorities were reportedly considering a five-day "circuit breaker".
However, the Herald Sun understands a longer lockdown is now on the table.
3AW understands the lockdown could be as long as 10 days.
There are close to 80 exposure sites across the city with Chief Health Officer Brett Sutton concerned over the length of time some cases have spent in the community.
Professor Nancy Baxter, head of the Melbourne School of Population and Global Health, told the ABC it was concerning identified cases were in the community for up to a week while "highly infectious" before testing positive.
Three bars in the Prahran and South Yarra area remain a concern to authorities, where one positive case spent nearly three hours until 4am at one of the venues.
The state recorded more than 40,000 tests in the previous 24 hours as the Melbourne community responded to a call for action from Mr Merlino.
Long queues at testing centres were seen again on Thursday.
Virgin Australia cancels Melbourne flights
Virgin Australia has cancelled more than 10 services in and out of Melbourne in the wake of the latest cases.
"Due to the evolving situation in Greater Melbourne, Virgin Australia will cancel more than 10 services" set down for Thursday, the carrier said in a statement.
"While most services in and out of Melbourne today are operating as normal, we are adjusting our forward schedule to better reflect changing travel demand and booking trends."
More to come.
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