There are 13 locations of interest so far in Coromandel and 10 in Auckland that were visited by a man who has tested positive for Covid-19.
The positive case, a 58-year-old man, was identified on Auckland's North Shore this afternoon.
The man, who was not vaccinated, visited Coromandel with his wife over the weekend and returned to Auckland on Sunday, Dr Ashley Bloomfield said.
His wife is fully vaccinated and has returned a negative test.
The discovery of the case prompted Prime Minister Jacinda Ardern to announce a three-day alert level 4 lockdown for the entire country starting from 11.59pm tonight.
The lockdown will last at least seven days for Coromandel and Auckland.
There are a total of 23 locations of interest with details of 14 released by the ministry so far.
A Grey Lynn cafe, Crumb, on Ariki St has been named as the first Auckland location of interest. The man was there last Thursday between 10am and 10.10am.
The locations of interest in Coromandel include the Star and Garter Hotel, the BP gas station and Jaks Cafe and Bar.
Anyone who has visited any of the locations is asked to self-isolate at home and call Healthline on 0800 358 5453.
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