PAPUA NEW GUINEA - More than 2,000 people were buried alive in the landslide that smothered a Papua New Guinea village and work camp on Friday in the country’s remote northern highlands, the authorities told the United Nations on Monday.

Government officials visited the disaster site on Sunday. And even as the official death toll jumped from a few dozen to 670, they warned that far more victims than expected appeared to still be caught under the rubble.

“The landslide buried more than 2,000 people alive and caused major destruction to buildings, food gardens and caused major impact on the economic lifeline of the country,” Lusete Laso Mana, an official in the national disaster center, said in a letter to the United Nations.

The letter stressed that rescue efforts continued to be a challenge. The main highway to the area is blocked, the letter said, and the ground remains unstable as water flows beneath the rocks, shifting land and “posing ongoing danger to both the rescue teams and survivors alike.”

The region, in Enga Province, is densely populated and located near the Porgera gold mine operated by Barrick Gold, a company based in Canada, in collaboration with Zijin Mining, a Chinese group. It is an area of remote and difficult jungle terrain, in a country of around 12 million people that sits just north of Australia. Tropical and divided along tribal, ethnic and linguistic lines, Papua New Guinea is rich in natural resources but largely underdeveloped, making it especially vulnerable to natural disasters, which strike frequently.

U.N. officials have been closely monitoring the situation. And with the latest estimate in hand, they emphasized that the need for assistance would be long-term and complicated.

“This situation necessitates immediate action and international support to mitigate further losses and provide essential aid to those affected,” said Anne Mandal, a spokesperson for the U.N.’s International Organization for Migration.

Over the weekend, the agency estimated that, on top of the toll of dead and missing, more than 250 houses had been abandoned as residents feared additional slippage, with roughly 1,250 people displaced.