Victoria has reported two new locally acquired Covid cases that have been linked to the MCG.
Victoria’s Covid-19 Commander Jeroen Weimar told reporters the latest Covid outbreak was "moving quickly".
"We're dealing with a very dynamic situation here, a very rapidly moving situation," he said.
"What we've got is two separate incursions into Victoria over the last three or four days, two chains of transmission, at least one is moving very actively and very aggressively across the state."
The new cases have emerged in Victoria after two removalists who travelled to the state from Sydney tested positive and a family of four also entered Victoria while infectious.
A teacher from Bacchus Marsh primary school, who lives in Barwon, was among the new cases announced on Wednesday, having reportedly attended an AFL match between Carlton and Geelong at the MCG on Saturday with an infected friend who lives at the Ariele Apartments, linked to the removalists.
New cases a 'serious situation'
Mr Weimar said the two new cases linked to the MCG, an adult and a child, were both sitting in the level two member's reserve area.
It is not believed they are known contacts of other positive cases detected at the MCG.
Mr Weimar said the new cases were sitting “in very different parts” of the MCG from the already identified cases.
“I think both these cases put us in a serious situation,” Mr Weimar added.
“The situation we were dealing with when we stood here 24 hours ago was all the contact up to that point had been between people who spent significant time together, known to each other.
“Our initial information is that the two new cases we have today are not known to the gentleman from the Ariele Apartments. That gives us significant cause for concern.”
“These are possibly two examples of stranger to stranger transmission between the individuals that we know about, and these two new cases.”
Mr Weimar said there were currently 6500 people in the state locked down as health authorities scramble to identify 2000 primary and secondary close contacts at the MCG.
"I'm very confident we have managed to get hold of people, unless their phone is dead and they're living under a rock," he said.
"So I'm confident around that. I think we've got a good response yesterday."
New Covid restrictions loom
Late on Wednesday, it was announced anyone aged over 12 will be required to wear a mask in all indoor settings, including schools and workplaces, unless an exception applies.
Masks must also be worn outdoors when social distancing isn't possible.
Earlier the AAP reported Victorian ministers and public health officials were holding meetings on Thursday to discuss reimposing restrictions such as caps on crowd limits and visitors permitted in homes.
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