New Zealand has put its largest city back into lockdown after recording four new Covid-19 cases, ending a 102-day streak without a local infection.

A three-day lockdown was swiftly imposed in Auckland after the cases were confirmed.

The four new cases are all members of a single-family. None had travelled recently.

Auckland residents will be asked to stay at home, large gatherings will be banned, non-essential businesses will be shut, and some social-distancing restrictions will be reintroduced in the rest of the country.

The South Auckland family have connections across Auckland.

The father, a man in his 50s, works the night shift at a facility in South Auckland. Three of his colleagues are currently awaiting their Covid-19 test results.

Health Minister Chris Hipkins has confirmed work colleagues of one of the infected family members are also showing Covid-19 symptoms.

There are reports at least two co-workers could be affected.