After 102 days without community transmission they are the first cases acquired from an unknown source.
New Zealand is now activating a resurgence plan.
Addressing NZ last night, Prime Minister Jacinda Ardern says we must take a "precautionary" approach as no origin had been found, or link to isolation facilities or people who work at the border.
As a result, Auckland moves to level 3 restrictions from 12 noon tomorrow. The restrictions will last three days until midnight Friday. The rest of New Zealand will move to level 2 at the same time.
"These three days will give us time to assess the situation, gather information, make sure we have wide-spread contact tracing," says Ardern.
Aucklanders are asked to stay home to stop the spread.
"Act as if you have COVID and the people around you have COVID."
Under level 3 in Auckland, people are to work from home unless they are essential workers, and stay in their bubbles.
Bars and restaurants will have to close, and restrictions come in place for funerals and weddings.
"Travelling into Auckland is prohibited unless you normally reside there and are travelling home."
People in Auckland but not from the city can return home, but must be aware of symptoms. Anyone with symptoms is advised to get a test
All key services, including pharmacies and supermarkets remain open. Food delivery is available under level 3. Childcare and schooling is only available for essential workers.
The government would provide the public with an update on Friday.
Ardern says she does not want to "predetermine" what might happen after that.