The government figure is about triple the United Nation estimate of 670 killed in the South Pacific island nation’s mountainous interior. The remains of only five people had been recovered by Monday, local authorities reported. It was not immediately clear why the tally of six reported on Sunday had been revised down.

In a letter to the UN resident coordinator dated Sunday and seen by The Associated Press, the acting director of the country’s National Disaster Center, Luseta Laso Mana, said the landslide “buried more than 2000 people alive” and caused “major destruction” in Yambali village in Enga province.

Estimates of the casualties have varied widely since the disaster occurred, and it was not immediately clear how officials arrived at the number of people affected.

The International Organisation for Migration, which is working closely with the government and taking a leading role in the international response, has not changed its estimated death toll of 670 released on Sunday, pending new evidence.

“We are not able to dispute what the government suggests but we are not able to comment on it,” said Serhan Aktoprak, chief of the UN migrant agency’s mission in Papua New Guinea.

“As time goes in such a massive undertaking, the number will remain fluid,” Aktoprak said.

UN Secretary-General António Guterres sent “heartfelt condolences” to the families of the victims and the people and government of PNG and said the UN and its partners are supporting the government’s response efforts, and “the United Nations stands ready to offer additional assistance at this challenging time,” UN spokesman Stephane Dujarric said on Monday.

The death toll of 670 was based on calculations by Yambali village and Enga provincial officials that more than 150 homes had been buried by the landslide. The previous estimate had been 60 homes.

The office of PNG Prime Minister James Marape did not respond on Monday to a request for an explanation of what the government estimate of 2000 was based on. Marape has promised to release information about the scale of the destruction and loss of life when it becomes available.

Determining the scale of the disaster is difficult because of challenging conditions on the ground, including the village’s remote location, a lack of telecommunications and tribal warfare throughout the province which means international relief workers and aid convoys require military escorts.

At least 26 tribal warriors and mercenaries were killed in a battle between two warring tribes in Enga in February, as well as an unconfirmed number of bystanders.

The national government’s lack of reliable census data also adds to the challenges of determining how many are potentially dead.

Earth-moving equipment used by PNG’s military was being transported to the disaster scene, 400km from the east coast city of Lae.

Traumatised villagers are divided over whether heavy machinery should be allowed to dig up and potentially further damage the bodies of their buried relatives, officials said.