Today there are 12 new cases and one probable case.

Cabinet's decided, for the next 12 days, Auckland will remain at Alert Level Three, and the rest of the country at Level Two.

Prime Minister Jacinda Ardern says officials are continuing to pursue theories to find the source of the latest cluster, but we may never know.

Authorities are also still trying to contact trace people linked to the new cases.

University of Auckland's Professor Des Gorman told Heather du Plessis-Allan that the structures were not in place to keep Covid out. 

"The rhetoric of a few weeks about the imminent likelihood of a community outbreak did not translate into action. If it had, there would have been screening of all the people in the border."

He also thinks that there should have been 30 testing stations set up in Auckland after the move to alert level 3. 

Gorman says that the theory that the outbreak started from surfaces at the Americold cool store is "silly". 

He believes it is more likely to have come from the border.

"If the sub-type of virus that the family has is not the sub-type of anyone who is currently in isolation, then it means that a person has walked into the country, did so undetected."