The Sydney coronavirus outbreak has grown by 10 cases to 21, prompting travel restrictions from Victoria and New Zealand.
Victoria is banning entry to non-Victorian residents who have been to seven local government areas in Sydney identified as hotspots, effective from 1am 23 June.
Victorian residents can apply for a red zone permit to enter the state, but will be required to quarantine at home for 14 days.
Meanwhile, New Zealand announced a pause on quarantine-free travel with New South Wales, effective from 9.59pm AEST (11.59pm NZT) on Tuesday.
The suspension will initially be in place for 72 hours while the source of new infections is investigated.
"This decision follows a public health assessment today which determined that while the overall risk to public health in New Zealand currently remains low, there are still several unknowns," a release from NZ's COVID-19 Response Minister Chris Hipkins said.
The decision on Tuesday night came as NSW Health added two flights to its list of close contacts, urging passengers on a Qantas plane from Sydney to Wellington on 18 June and an Air New Zealand flight from Wellington to Sydney on 21 June to get tested and isolate for 14 days.
NSW's official case tally for Tuesday was five cases, including two announced on Monday. Seven additional cases were detected after the 8pm cut off and will be included in Wednesday's figures.
NSW Premier Gladys Berejiklian announced extended mandatory mask restrictions on Tuesday, with all people in Greater Sydney, Wollongong and Shellharbour required to wear a face mask while indoors for an additional seven days.
The three new cases included in Tuesday's numbers include a woman in her 60s from the Illawarra, a woman in her 40s from Sydney's northern suburbs, and a woman in her 20s from the eastern suburbs who is believed to have contracted the virus through "fleeting contact" while working at Westfield Bondi Junction.
Chief Health Officer Kerry Chant said the first two cases were close contacts of existing cases but said the third was of concern.
In response, health authorities are urging anyone who was in Westfield Bondi Junction, including the car park, at any time between 12 and 18 June to come forward for testing.
Of the seven cases detected overnight, six are household contacts of previously identified cases and have been isolating.
The seventh case is a child who attends St Charles Catholic Primary School in Waverley and the source of the infection is currently unknown.
Parents are being urged to wait for advice from the school and health authorities to ensure students are able to return home safely.
"Unfortunately, a number of people who contracted the virus have done so in a very fleeting way," Ms Berejiklian said.
"A very fleeting exchange or a very fleeting coexistence has actually allowed the virus to transfer and highlights how contagious it is."
There are currently no plans for a lockdown to be introduced, Ms Berejiklian said, because all but one case has been linked to known infections.
"If that changes, if we suddenly have a number of unlinked cases and if we suddenly have them outside the geographic region they are concentrated in then we will obviously adjust the health advice and we will respond to that," she said.
Testing numbers grew to more than 28,000 in the 24 hours to 8pm on Monday, up from 25,000 the previous day.
More locations were added to the on Tuesday afternoon. The sites include locations in the Sydney CBD, Bondi Junction and Mascot.
Meanwhile, the Northern Territory has declared the Waverley and Woollahra local government areas COVID-19 hotspots, meaning anyone who arrives in the NT after visiting to those areas must quarantine at Alice Springs or Howard Springs facilities.
Health authorities are urging anyone with even mild cold-like symptoms to come forward for testing and isolate until a result is returned. Residents of Sydney's eastern suburbs and Wollongong have been asked to be "especially vigilant".
