Ethnic Vietnamese activists missing in Cambodia

Ethnic Vietnamese activists are reported missing in Cambodia, raising concerns over their safety, human rights, freedom of expression and treatment of minority communities.

Catholic prayer vigils held for Australian, Norwegian men who failed to board their plane out of Phnom Penh, Viet Tan says

Two members of Viet Tan, Nguyen Duc Thuan and Tran Hiep, have been missing in Cambodia since Sept. 18, 2026. To date, their families and colleagues have received no information about their whereabouts. (Photo:viettan.org)

Two ethnic Vietnamese Catholics — an Australian and a Norwegian — have gone missing in Cambodia after meeting with activists from the Viet Tan movement, which advocates for a free and democratic Vietnam.

Duy Hoang, executive director of Viet Tan, said Tran Hiep, also known as Ho Pham Hiep Huy, 51, from Melbourne and Nguyen Duc Thuan, 52, from Oslo, had been missing in Cambodia since Sept. 18 and their families had not received any information since then.

“Nguyen Duc Thuan and Tran Hiep are long-time human rights defenders. Clearly, this is not an ordinary missing persons case. They disappeared 10 days ago. Friends and family want to know: Where is Thuan? Where is Hiep?

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“If Vietnamese intelligence agents operating in Cambodia had a hand in their disappearance or abduction, then this must be brought to light and the Hanoi government must be accountable for acts of transnational repression,” Hoang told UCA News.

Both men flew into Phnom Penh on Sept. 15 from Bangkok and were scheduled to leave Sept. 19, but they never boarded their flights, Hoang said, adding Hiep last spoke with his mother on Sept. 18 about an upcoming family birthday.

United States-based Viet Tan is banned in Vietnam and is officially designated as a terrorist organization. Its members have been handed lengthy jail terms for plotting to overthrow the country’s one-party communist government.

However, human rights groups are increasingly concerned about transnational repression, alleging Southeast Asian countries were turning a blind eye to foreign governments, extending their reach beyond national borders to harass and silence their critics.

“While details are still a bit sketchy, the sudden disappearance of these two Viet Tan activists has all the hallmarks of transnational repression,” said Phil Robertson, Director of Asia Human Rights and Labour Advocates.

He urged Australia and Norway to mount “full diplomatic pressure,” and demand answers from the Cambodian and Vietnamese authorities, saying the government of President To Lam viewed the Viet Tan as a major threat to its efforts to control the Vietnamese diaspora abroad.

“Given the long relationship between de facto Cambodian leader Hun Sen and Vietnam, there is little that would oppose Vietnam from mounting an operation to snatch these two men in Cambodia or at the border.

“I suspect that in a couple of months, we will see these two men pop up in Vietnamese custody, with authorities claiming they tried to illegally enter the country,” Robertson said.

“These two activists must be found and allowed to return to their families in Oslo and Melbourne.”

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Hoang said Viet Tan members in Vietnam and around the world had for many years connected regularly with activists and civil society organizations to exchange ideas and offer mutual support while Thuan and Hiep were also active in their local communities.

“We hope that Thuan and Hiep are safe and will soon return home to their families. Both are Catholics. They have also been active in advocating for religious freedom in Vietnam,” Hoang said. 

“Since news of their disappearance became known, several Catholic congregations have planned prayer vigils for their safe return and posted messages in support.”

Hoang said Viet Tan was working closely with the Norwegian Ministry of Foreign Affairs and the Australian Department of Foreign Affairs and Trade in trying to locate the pair.

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