The Covid-19 Response Minister says authorities are working to figure out how far Covid-19 has spread.

New Zealand has 39 cases of Covid-19 today, 30 in Auckland, nine in Waikato.

Two cases spread past areas that aren't in Alert Level Three and a potential Covid-19 case was detected in Whangarei. 

The person, who is now in Auckland, returned a weak result and will take another test.

Chris Hipkins told Heather du Plessis-Allan it may be nothing.

“It was a very what we call a high CT value, which means a very, very weak test. And we have had those in the past where when a retest is done it’s come back negative.”

Meanwhile, Waipa Mayor Jim Mylchreest says the entire North Island should be locked down.

Hipkins says it's an evolving process.

"We'll make further decisions. As our case investigators provide further information, we'll make further decisions on that in the next 24 hours."

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