Australian authorities in an unprecedented announcement decided to seal off the borders of the state of Victoria.
The border closure would come into effect at 11:59 pm local time on Tuesday.
The 6.6 million people living in Victoria would be cut off from the rest of the country after 127 new cases were reported through Melbourne, including clusters many densely populated apartment blocks.
Victorian Premier Daniel Andrews described the decision to close off the state as “the smart call, the right call at this time, given the significant challenges we face in containing this virus”.
Andrews added that food and toys had been delivered to families while mental health and other medical support was being provided as officials sought to test every resident over the coming days.
After weeks of easing virus restrictions, Melbourne has seen a huge spike in community transmission. Stay-at-home orders were imposed on dozens of suburbs and, on Saturday, 3,000 residents of nine densely populated public housing estates were suddenly put under a total lockdown.
Coronavirus has infected 2,663 people and killed 22 in Victoria.
All of Australia reported more than 8,500 cases including 106 deaths.