Two teenagers were among six people missing after a landslide hit a busy campground on New Zealand’s North Island, authorities said on Friday, as rescuers worked round the clock to locate survivors under the rubble.

Heavy rains triggered Thursday’s landslide at Mount Maunganui on the island’s east coast, bringing down soil and rubble at the site in the city of Tauranga, crowded by families on summer holidays, but no deaths have been confirmed.

“We have 25 personnel working with contractors and their diggers and police dogs, as well as police operations to ensure that every inch of soil removed is worked through,” said David Guard, a fire and emergency official.

The scale of the disaster and risks at the site could delay the rescue effort, however, New Zealand Police Commissioner Richard Chambers told the New Zealand Herald newspaper.

“It could be days, and we appreciate that everybody is anxious and waiting for their loved ones, and for some answers, but we also have to be very careful,” Chambers said.

The youngest of the missing was aged 15, police commander Tim Anderson told a press conference, adding that authorities were scrambling to contact an additional three people.

“We don’t believe they’re here, but we’ve still got to do that inquiry,” Anderson said.

No signs of life have been detected from the rubble since voices were initially heard by first responders on Thursday, Anderson added.

Video images showed recreational vehicles and at least one structure crushed at the campsite.

Prime Minister Christopher Luxon visited the site on Friday and met affected families. “They are grieving incredibly hard, and I know that New Zealand grieves with them,” he said.

Luxon promised government funds for affected areas once they assessed damages.

Fielding reporters’ questions about why the campsite evacuation had not been swifter, he said there would be a public review into the circumstances.

The heavy rain that lashed almost the entire eastern seaboard of the North Island unleashed another landslide in the neighbouring suburb of Papamoa, killing two.

One was a Chinese citizen, Chinese Ambassador Wang Xiaolong said on X on Friday.

Roads stayed closed in some of the worst-hit areas, cutting off some towns from contact by land.

On social media, civil defence authorities in the district of Tairawhiti warned people seeking to collect emergency supplies of water and food not to pick their way over landslides, as it risked triggering further movement of rock and soil.