Premier Daniel Andrews has confirmed the surging coronavirus clusters Victoria is now battling have come from New South Wales, but how they started still remains a mystery.
On Saturday's press conference, Mr Andrews responded to a question asking where the current cases have stemmed from, saying it's 'definitely' linked to the NSW outbreak.
"There's about 20 per cent of cases where you can't get an exact match," he said.
"It's definitely New South Wales. It's definitely Delta. The question is to what extent is it actually linked to. "
Victoria records 29 new cases
Victoria recorded 29 new cases of Covid-19 on Saturday as the state endures its sixth lockdown.
Mr Andrews said it's "significant" to see this many cases, although warned he's worried about the origins of some cases.
"They are linked to outbreaks and we don't know where those two outbreaks started, so they are mystery cases that sit behind this," he said.
"The cases we have found since are linked to others that we knew. They have been out in the community and... there is a certainty that there are more cases out there. That is why getting tested when you have any symptoms is so important."
Of the 29 new cases, four are family members in the Maribyrnong cluster. The four new cases all family members of the index case, including two people who flew into Melbourne from Sydney hotel quarantine on July 15 on flight QF445.
The other 25 are associated with the Hobson's Bay cluster.
'Too early' to say when lockdown will end
Mr Andrews said it was too soon to tell if Victoria's lockdown would end after seven days.
"It's too early for us to say," he said.
"I'd much rather have no cases than 29 cases. But at the same time, this is an exercise in finding cases."
He urged anyone with symptoms or who has visited any of the exposure sites to come forward and get tested immediately.
"If you've got symptoms, you have got to assume that you have got Covid, please come to get tested,” he said.
“There is arguably nothing more important than people getting tested as soon as they register symptoms. That is how we shut this down.
“That is how we get out in front of it. That is how we get our community and our economy opened up again.”
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