There are 78 new cases of Covid-19, including 73 confirmed cases and five new probable cases, Director General of Health Ashley Bloomfield says.
Details of these cases will be on the Ministry of Health website as details emerge.
There are 27 people who have recovered.
Seven people are in hospital and are stable. None are in ICU.
Yesterday 2417 tests were processed nationwide, taking the total number of tests to 12,683. About 1400 tests have been done daily in the last week.
People who have been tested must self-isolate from those in their household while awaiting the results of their tests.
Most cases are still linked to overseas travel or to existing clusters of confirmed cases, such as Marist College in Auckland and the world conference in Queenstown.
There are also possible clusters around a travel group to the US as well as a rest home in Hamilton.
More information will be provided about those clusters on the MoH website.
Bloomfield said all people should be able to access pharmaceuticals they need, despite the stockpiling in recent days.
From tonight, pharmacists can only dispense one month supplies of pharmaceuticals, or three months for oral contraceptives.
He added that there were no significant shortages at the moment, but the measure was a precaution to ensure supplies of essential medicines.
"These are unprecedented times,"he said.
He added that the number of cases will continue rising for the next 10 days, but if people stayed at home and self-isolated properly, the number will come down.
168 Kiwi travellers in quarantine
Police Commissioner Mike Bush said day one of the nationwide lockdown showed that most New Zealanders were complying.
He said the police had to ensure safety, and to ensure the country was sustainable.
"Stay home to stay safe. If we don't comply, the consequence of that is people will die."
Police were being "very visible" and initially it was about education and engagement and encouragement.
Police were telling people what was required of them, and were challenging people about whether they were going about essential things if they were outside their homes.
"People everywhere across New Zealand for their friends and everyone else to keep each other safe," Bush said.
Bush said New Zealanders returning home since 2am this morning are being triaged.
"If you have any symptoms, you will be taken by health people to a place of quarantine."
Hotels and motels near Auckland Airport were being used, he said.
"If you have a place to go, we will help you get there. If you have friends coming to pick you up, only one person in your bubble will be allowed to take you," Bush said.
He said 360 people had come through Auckland Airport this morning, and it had gone smoothly, notwithstanding a few "speed bumps".
He said eight of the 360 arriving this morning had been quarantined; 160 didn't have plans and were also placed in quarantine.
e said of the 168 in quarantine, 160 did not have proper plans and their travel to a suitable place was being facilitated.
Those who had proper plans would be visited by police to ensure they were sticking to those plans.
Services that were open but not essential were being closed by police, he said.
Bush made it clear that people driving to a park had to "keep it local" and people should not be driving "willy nilly" all over town.
Gunman's guilty plea
Bush also commented on the Christchurch mosque gunman pleading guilty and paid tribute to the courage of the March 15 victims. He said the admission this morning meant they wouldn't have to relive the events of that traumatic day.
He also praised the police and prosecuting team involved in the case.
On the guilty plea, he said it was a "very fast-moving piece", and police had empathy for the people involved.
Sentencing would happen when victims could attend, he said.
He said he could not comment on why the plea had changed to guilty today.
He said the victims not having to relive the trauma was the most important impact of today's plea.
Some police resources would now be able to be redirected to help with the lockdown, he said.
The Alert Level 4 nationwide lockdown came into effect at 11:59pm yesterday, and police are on patrol around the country to ensure people are staying at home unless they have a valid reason to be outside.
Bush said this morning some people were not even aware that a nationwide lockdown had been ordered.
He said people this morning were unaware of the lockdown, and if people breached the requirements, they will be warned and their details taken.
"If people won't comply, we do have the authority to detain them, take them to our place," and give them time to contemplate their decisions.
People will be prosecuted for "serious" breaches.
He was not aware of any arrest or warnings.
People who were charged might face six months' jail for, for example, obstructing police.