Rights group Amnesty International on Friday urged Cambodia to immediately stop the ongoing "mass forced evictions" of 10,000 families from the Angkor Wat temple complex.
The Cambodian government late last year ramped up the relocation of families living within the sprawling UNESCO world heritage site to a new community being built on former rice paddies 25 kilometres (15 miles) away.
Authorities say they are acting to protect the ruins by moving squatters whose informal settlements are damaging the local environment by producing rubbish and overusing water resources.
The government says people are moving voluntarily but Amnesty said its research found that villagers faced "implicit threats if they did not move".
It said those affected were not properly consulted or given enough notice.
"These are forced evictions in disguise and on a mass scale. People were pressured to volunteer and made to feel fearful of reprisals if they refused to leave or challenged the evictions," Ming Yu Hah, Amnesty's deputy regional director for campaigns, said in a statement.
"The Cambodian authorities should immediately halt this harmful eviction drive that seriously risks impoverishing thousands of families," Ming Yu Hah added.
The ruined Angkor Wat temples, half-swallowed by the jungle, are the country's top tourist attraction.
Families being moved are given a 20-by-30-metre plot of land, $350 cash, 30 pieces of tin roofing material and access to a welfare card -- but they have to build their own houses.
Long Kosal, a spokesman for the Apsara National Authority, which manages the archaeological park, refused to comment on Amnesty's statement.
Prime Minister Hun Sen -- who has ruled the kingdom with an iron fist for nearly four decades -- has warned that Angkor Wat will be withdrawn from the world heritage list if villagers were not relocated away.
UNESCO guidelines say relocations should be carried out with the consent of the population concerned, and that local communities should be the primary beneficiaries of tourism from heritage sites.