People living on parts of the coast were told to evacuate their homes and get to high ground immediately following the magnitude 8.1 quake shortly before 8pm GMT, after it hit off the north-east of the country near Kermadec Islands Region.
At around 10pm GMT people on the ground began reporting that the sea was going out in Whangarei, with streams and rivers also emptying.
An hour later the first of the waves were spotted racing towards the coast.
Hundreds of residents were chaotically fleeing homes, workplaces and schools to get to higher ground following the warning.
A Whangarei worker told the publication: “(There were) heaps of people standing on the street outside their workplaces.”
Parents spoke of their desperate attempts to move through grid locked traffic to get their kids from school.
Raiha Jackson, from Whakatane, said people were rushing with their children into fields away from the coast because the roads were too busy.
Ōhope resident Leslie Peake said fleeing cars were stuck bumper-to-bumper on roads out of the town, with the hilltops packed full of people looking out to the sea.
The evacuation order stands for everyone on the east coast of the North Island from the Bay of Islands to Whangarei, from Matata to Tolaga Bay and Great Barrier Island.
New Zealand’s National Emergency Management Agency said the first waves would arrive on New Zealand’s north shores by about 9:45 a.m local time.
Residents have also fled to the tops of tall buildings in American Samoa, while a tsunami watch order has been issued in Hawaii.
The National Emergency Management Agency has urged people to run or cycle if it will help them get to safety quicker.
“The first wave may not be the largest,” the agency warned.
“Tsunami activity will continue for several hours and the threat is real until this warning is cancelled.”
It added: “DO NOT WAIT. A damaging tsunami is possible.”
Ōpōtiki mayor Lyn Riesterer said the town was evacuating.
“Most people are underway, all moving out,” Riesterer said.
“All of the alerts went off on mobile phones at the same time so everyone is moving.”
The evacuation order overrides any Covid restrictions in place.
According to USGS the latest quake to hit off the Kermedec Islands was magnitude 8.1 and 19.4km deep.
Earlier a 6.9 magnitude earthquake also hit off the coast, followed by a 7.4 tremor.
Prime Minister Jacinda Ardern said: “Hope everyone is ok out there – especially on the East Coast who would have felt the full force of that earthquake (the map here shows just how many people were reporting it across the country).”
Following the second quake one Twitter user wrote: “That was a long, strong earthquake! Wide awake!”
Another said: “The way the entire country felt it is….slightly concerning.”