Strong surges in the Far North that accumulated from remnants of a tropical cyclone in the Pacific and Tonga's volcanic eruption prompted evacuations and caused boats to sink overnight.
Yesterday, a tsunami warning for the north and east coasts of the North Island was issued after underwater volcano Hunga-Tonga-Hunga-Ha'apai erupted yesterday and triggered a tsunami in the Kingdom.
The advisory has this morning been extended to the west coast of the South Island.
Police said emergency services received a number of calls from people based in the Far North between 11pm and 12am, including Te Rere Bay and Shipwreck Bay.
Northland Civil Defence spokesperson Murray Soljak said more than 120 people through the Far North were evacuated last night due to the powerful waves.
Police, Fire and Emergency, and Coastguard also assisted with evacuations of boats moored at Tūtūkākā Marina last night.
A number of boats and moorings were damaged by large waves washing ashore.
He said damage caused to boats in Tūtūkākā Marina last night were due to a single wave, however, surges along the coast are continuing at regular intervals.
Some of the vessels broke loose from their moorings due to the incoming surge of water, he said.
"Unfortunately a number of boats have sunk as a result of that; there's quite an extensive clean-up underway."
A campsite at Mahinepua Bay was inundated, about 50 people were in the camp at the time and all were accounted for.
Souljak said while the ocean may look calm, it was unpredictable and people should stay away.
The power of the surge at Tūtūkākā Marina saw boats go over each other and travel at 15 knots per hour.
Dive Tūtūkākā owner Kate Malcolm said she had pulled at least four boats from under her own vessels this morning and expected at least 20 others had been damaged.
She said the sound of the wave was the worst thing she had heard.
"It was dark at the time, and we've still got Cyclone Cody doing it's little dance for us but the sound I think is the worst thing - the creaking and the cracking and the breaking of the wood and the pinging of the wires, that's what you hear, and then the noise and the rumble."
Malcolm believed it will be at least a week until she could assess her own vessels.
Polystyrene and boat debris filled Tūtūkākā Marina this morning after the powerful wave last night.
Boat owner Harvey Ferguson is worried about damage from waves to come, now that moorings at Tūtūkākā Marina are broken.
Ferguson said the damage was not over with powerful surges expected to continue.
"If the last tsunami did this and there's others [surges] coming down, all these boats here are gonna crash.
"All them boats are going to end up smashed up into each other, totally. There's already carnage and boats sunk all over the marina."
Ferguson said he was distraught at the thought of losing his boat, which he considered a member of the family.
"The boat is unreplaceable as far as I'm concerned," he said.
"You've had a boat for 30 years - and I've just had a major refit. About $100,000 spent on it two months ago and put back in the water for the game fishing season and here it is in danger, real danger."
Gaeline Phipps was onboard her vessel when the wave hit.
"I was lying in the cabin, just listening to this unusual sound of the water - sounding like a river, a gurgling river - and it was swishing around the boat and I was wondering ... goodness what's going on and thinking there's no sirens or warnings," she told RNZ.
Phipps said shortly afterwards her daughter came running down saying she had seen a boat going past by the light of the port lights and that the water "looked like a spa pool".
Phipps said no-one was injured but a whole pier had disappeared, sinking the boats moored to it, and the fuel pier had also floated off.