Two ethnic Jarai Montagnards claiming to have fled religious persecution in Vietnam may have been arrested by local police in Ratanakkiri province, a rights worker has said.

The UN is seeking to intervene in the case and has requested government cooperation while several more Christian Montagnards are thought to have crossed into Cambodia in recent days, sources told the Post.

“If the arrests were done in secret, then it is a severe violation of their human rights and rights as refugees,” said Chhay Thy, provincial coordinator for local rights group Adhoc.

The Vietnamese authorities in neighbouring Gia Lai province sent a report to their Cambodian counterparts saying that 16 Montagnards had fled to Cambodia, but rights workers and locals have only been in contact with 13 of the refugees, he added.

“We knew about and found only 13 people; we did not know about the other three,” Thy said.

The Montagnards – an umbrella term for ethnic minorities in use since the French colonised Vietnam – who recently fled to Cambodia are all ethnic Jarai, a minority group prevalent in northeastern Cambodia.

Sev Fin, a village chief in O’Yadav district’s Pak Ngai commune, said he understood that two Jarai were arrested and were due to be deported to Vietnam.

“The police officials and security forces arrested them and they will likely send them back to Vietnam,” he said.

But the authorities in Ratanakkiri denied the reports.

Nguon Keurn, Ratanakkiri provincial police chief, said the reports of arrests had been confused with a group of ethnic Vietnamese who had farmed in Cambodian territory and had been briefly detained Tuesday.

“The four people were not Montagnard refugees,” he said. “More Montagnard people might come, but we do not know how many.”

Another source with knowledge of the case, who requested anonymity, said the arrests were unconnected to the Montagnards.

A UN official in Cambodia, who also requested anonymity because he was not authorised to talk to the media, said the UN was seeking to visit the Montagnards, who have been hiding out in the forest since they arrived.

Bushra Rahman, a spokeswoman for the Office of the High Commissioner for Human Rights, said: “The UN is in contact with the competent authorities toward finding a solution.”

Keurn said the police would cooperate with the UN.

Phil Robertson, deputy director of Human Rights Watch’s Asia division, said the Montagnards had likely fled state-sanctioned persecution.

“Vietnam continues to discriminate against and persecute Montagnards on political and religious grounds, arresting those considered hostile to the government and shutting down Protestant and Catholic house churches not affiliated with state controlled religious front groups,” he said.