More than 40 people are facing prosecution for flouting lockdown rules, as police gear up for checkpoints over Easter.
New Police Commissioner Andrew Coster said New Zealand was now at a stage where people knew the rules - but some were flouting them anyway, including surfers.
There have been 45 prosecutions of people breaching lockdown rules - up from 16 just days ago.
Another 367 people had been issued warnings, up 76 from yesterday.
There have been a total of 37,000 reports of breaches, Coster said.
"We have identified spitting as an escalating risk to both police officers and the community."
Eight police staff had been spat at - which potentially constituted a charge of infecting with disease, which under the Crimes Act, carries a maximum penalty of 14 years imprisonment.
Anyone who spat deliberately on others was "thoughtless" and "malicious", he said.
"It is completely unacceptable."
The people spitting either told officers they had, or had symptoms of Covid-19.
Coster said that this weekend some people might think New Zealand was doing well in its fight against Covid-19 so it was okay to go out.
He said that was not the case.
Anyone planning to get away for a Easter break should "change your plans immediately".
Coster thanked the majority of New Zealanders who are following the lockdown rules.
But a minority continued to break the rules, he said.
So far, Civil Defence has provided 7727 food parcels.
Stuart-Black reiterated that yesterday the national state of emergency was extended for another seven days. This is the second time it had been extended.
PM: Obey the lockdown over Easter
Prime Minister Jacinda Ardern has already said she expects everyone to continue to obey the lockdown rules, even though religious congregations in particular will be disappointed.
But she said today that people should hold virtual congregations and stay connected, even though churches will be closed.
Police have the power to set up road blocks and checkpoints but in an interview earlier today Coster said he would not be saying where those checkpoints will be.
He also told RNZ that police had focused on education early in the lockdown, but that focus will turn towards enforcement now that it was less of a reasonable excuse to say the lockdown rules were unclear.
The national state of emergency was extended yesterday, which essential empower authorities to act in any way necessary to prevent further outbreak of Covid-19.
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New guidance on police powers reveal that under alert level 4 police may do "anything reasonably necessary, including the use of force, to compel, enforce, or ensure compliance" of the lockdown measures.
They also have the power to "enter, remain and inspect" any household or office that is suspected of housing an unsanctioned gathering.
"There is a power to stop and inspect any vehicle, and enquire into the purpose of travel," the advice states.
It also says police have the power to enter and inspect a premises if they have "reasonable grounds" to suspect there is a large gathering of people from different bubbles.
The advice states they are not allowed to set up a police roadblock for usual police purposes.
Coster started in the commissioner role last week and recently shaved off his beard in solidarity because face masks did not fit well over facial hair.