New Zealand's Prime Minister Jacinda Ardern on Sunday (February 14) announced a three-day lockdown in the country's biggest city Auckland, after three new COVID-19 cases emerged.
They're the first local infections detected since late January.
Arden said level 3 restrictions will require everyone to stay home except for essential shopping and essential work.
"Three days though, should give us enough time to gather further information, undertake large scale testing and establish if there has been wider community transmission. That is what we believe the cautious approach requires and it's the right thing to do."
She went on to tell the news conference in Wellington: “We have stamped out the virus before and we will do it again."
Sunday's cases were traced back to a couple and their daughter in Auckland.
Health authorities are trying to find out whether they involve any of the new, highly infectious variants that have been found in other countries including the UK and South Africa.
The COVID-19 alert for the rest of New Zealand was raised to level 2, with all gatherings limited to 100 people, including at restaurants and cafes.
The country is due to start inoculating its population of 5 million with the Pfizer-BioNTech vaccine from next Saturday.