Australia's second most populous state Victoria on Monday said it was investigating two suspected positive COVID-19 cases in Melbourne, which if confirmed would be the first community transmissions in the state in almost three months.
Under the restrictions, masks will again be compulsory in all indoor settings.
Private gatherings indoors will be limited to five people and public gatherings will be limited to 30 people.
The ACT had previously lifted its travel restrictions with Victoria on Monday, before the new cases were recorded.
The positive case sat in zone four, level one, of the Great Southern Stand, at the Punt Road end of the ground, to watch Collingwood's nail-biting loss to Port Adelaide on Sunday, the Department of Health said.
"Hopefully, they have a good sense of whose been exposed, what the risks are, so they can identify those people they need to call into quarantine, rather than go into something more wide-spread", she said.
Schools and workplaces remain open and density requirements at restaurants and bars remain unchanged but the government is seeking advice on weddings and sporting and cultural events.
They are all family contacts of the fifth case - a male aged in their 60s - announced this morning, bringing the total of cases in this outbreak to nine.
The club has said it is conducting its own contact tracing, and will request Football Victoria to move the fixture.
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A medical worker prepares a dose of COVID-19 vaccine at a drive-thru vaccination site in Toronto, Canada, on May 22, 2021. Grindrod mentioned the risk is about one in 60,000 for the first dose, but one in 600,000 for the second dose.
"This is not a time to be complacent", Victoria's health minister, Martin Foley, told reporters. This earlier case was linked back to transmission occurring at a South Australian quarantine facility.
Chief Health Officer Jeanette Young says today's new cases in Victoria meant they needed to take action.
"It's possible there's another missing link", Professor Sutton said.
The statement from Hipkins on Tuesday said that while the new case announced in Melbourne was not unexpected, New Zealand officials had assessed the situation and the most cautious option was to pause the travel bubble with Victoria "as there are still several unknowns with the outbreak".
Tier one exposure sites include: Nando's Epping, Dalton Road between 8pm and 9.20pm on Wednesday, May 19; Highpoint Shopping Centre on May 20 between 5pm and 8pm; Jump Swim School at Bundoora on Friday, May 21 between 8.55am and 10.15am; Woolworths Epping North between 4.45pm and 5.45pm on Saturday, May 22.
Anyone who has been at a location of interest has also been banned from travelling to New Zealand, irrespective of whether they have travelled interstate since then.
According to New Zealand's Ministry of Health, this means that these specific people are ineligible to travel to Aotearoa within 14 days from exposure - even with a negative Covid-19 test.
More household contacts of the new cases have been put into isolation despite testing negative so far.