The Montagnard tribes-people come from rural Vietnam
The United Nations refugee agency UNHCR is pulling out of its programme to repatriate around a thousand Vietnamese tribal people who fled to Cambodia last year.
The decision follows an incident on Thursday when UNHCR staff working at a refugee camp in Cambodia were attacked after trying to prevent Montagnard refugees from being forcibly returned home.
More than 400 Vietnamese arrived at the Cambodian refugee camp in Mondulkiri on Thursday.
They threatened and manhandled refugees and the UNHCR staff trying to protect them, according to the agency.
Exodus from Vietnam
Last year, more than 1,000 Montagnard tribes-people fled from Vietnam to Cambodia after a military crackdown following a series of protests in the central highlands.
In January, the UNHCR signed a controversial accord with Hanoi and Phnom Penh to start a repatriation programme.
But this was suspended after Vietnam refused permission to visit the families of potential returnees.
In all, only 15 people have returned under the official programme.
In this latest incident, the UNHCR says that Montagnard refugees were subjected to unacceptable levels of coercion to repatriate, and that the lives of UNHCR staff were threatened when they tried to intervene.
According to the refugee agency, the Cambodian officials who are normally present on the site were absent or did not respond.
The Vietnamese Government denies that it sent agents to intimidate the refugees, saying that those who entered the camp were relatives who had come to encourage them to return home.