Two days of heavy rains in northern New Zealand has triggered landslides, killing two people in a severely damaged house and leaving several unaccounted for at a campsite.

Emergency services were working to locate survivors at Mount Maunganui, a popular tourist spot on the northern coast of New Zealand.

"I can't be drawn on numbers," Assistant Police Commissioner Tim Anderson told reporters at the scene. "What I can say is that it is single figures."

Rubble barreled down on the Beachside Holiday Park at 9:30 a.m. local time on Thursday (2030 GMT/UTC Wednesday).

Hundreds of people were at the campsite at the time of the incident, the local mayor said.

New Zealand's Fire and Emergency commander William Pike said there were initially signs of life at the site of the landslide, but not recently, according to local news site, Stuff.

Fire crews and other members of the public had heard voices under the rubble, according to Fire and Emergency Commander William Park.

But rescue workers had to withdraw because of the unstable ground and nobody had been rescued yet, Stuff said.

"This is a complex and high-risk environment," added Megan Stiffler, a ‌fire and emergency services official. "The teams will be operating overnight until the search is complete."

Sniffer dogs are at the scene.

Children among those missing in landslide

Police said the number of people missing was in the single figures, with children apparently among them, local media report. 

One witness, Nix Jaques, told Radio NZ she heard an incredibly loud noise as she was ⁠about to walk up a mountain.

She saw land come down on cars and on toilet block, she said. 

"I believe there were ‌some people in ⁠the showers, and it shifted a campervan, there was a family with a campervan."

Two killed in separate landslide

Police later said that two people had died in Welcome Bay, Papamoa, after a house was extensively damaged by a landslide. Their bodies were recovered after rescue efforts. 

Separately, another person was missing after being washed away in their vehicle north of Auckland, the main city on New Zealand's north island.

"The weather events of the past 48 hours have been a profound tragedy, claiming lives and devastating livelihoods," Prime Minister Christopher Luxon said. 

Opposition Labour Party leader Chris Hipkins similarly offered his "deepest sympathy to those who have lost loved ones or are still waiting for news, and to everyone who has been forced from their homes or injured."

Heavy rains along the east coast of New Zealand's North Island over a period of around 48 hours have caused widespread damage and left thousands without power. Fire and Emergency NZ said its crews had responded to 236 weather-related call outs since the early hours of Thursday. It warned people not to drive through floodwaters.

Edited by: Roshni Majumdar, Darko Janjevic