Concern is mounting for an Australian activist who has gone missing in Cambodia after a human rights organisation alleged he was abducted by Vietnamese authorities in an apparent case of “transnational repression”.
Tran Hiep, a democracy advocate, had been expected to meet his wife, Chloe Dang, in Bangkok after travelling to Phnom Penh to meet human rights defenders.
However, the 50-year-old Melbourne resident failed to board his flight and has not been heard from since September 18.
Mr Hiep, founder of the Australian Alliance to Combat Human Trafficking, was in Cambodia with Vietnamese-Norwegian human rights activist Nguyen Duc Thuan. The pair had planned to provide training for dissident Vietnamese activists.
Viet Tan, a pro-democracy political party representing the Vietnamese diaspora, has accused Vietnamese authorities of kidnapping both men. It rejected claims that they had illegally crossed into Vietnam from the Cambodian border.
The advocacy organisation, which counts Mr Hiep and Mr Thuan among its members, said the men had no intention of entering Vietnam. It alleged that authorities had abducted them in Cambodia and used fabricated charges to conceal an act of “transnational repression”.
“This is a blatant fabrication intended to conceal the fact that the Viet Tan members were abducted in Cambodia and forcibly taken to Vietnam,” the group said in a statement issued on Monday night.
AAP has contacted Vietnamese authorities for comment.
Tran Hiep, founder of the Australian Alliance to Combat Human Trafficking, was in Cambodia with Vietnamese-Norwegian human rights activist Nguyen Duc Thuan to train dissident Vietnamese activists
Viet Tan has urged the Australian and Norwegian governments, along with human rights organisations, to demand the Vietnamese government release both men immediately and without conditions.
“Mr Thuan is diabetic and requires daily insulin injections. He must be guaranteed full access to medication and medical care,” the organisation said.
Ms Dang said she was deeply concerned about her husband’s safety.
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“My family and I are really worried about his safety, and we just want to know where he is and what happened to him,” she told AAP at Bangkok airport before boarding a flight to Melbourne.
“My husband deserves protection, and I really hope the Australian government will continue to put pressure on Cambodia to investigate and find out where he is right now.”
Vietnam has intensified its crackdown on dissidents in recent years, with more than 55 activists arrested under broadly worded criminal laws in 2025.
Civil society organisations and United Nations human rights experts have repeatedly raised concerns about increasing co-operation between Vietnamese authorities and neighbouring governments in targeting activists.
“Their disappearance is not an ordinary ‘missing person’ incident. Both men are long-time human rights advocates and Viet Tan members,” the organisation said.
Democracy campaigner Tran Hiep had planned to meet his wife, Chloe Dang, in Bangkok after travelling to Phnom Penh to meet human rights defenders
Ms Dang, 36, said the uncertainty surrounding her husband’s disappearance had taken a significant psychological toll.
“It’s been 11 days and I’m really in the dark,” she said, choking back tears. “I don’t know where he is or how he’s doing – it’s driving me crazy. Everything is really uncertain.”
The Australian government confirmed consular officials were in contact with Ms Dang but declined to comment further.
‘The Department of Foreign Affairs and Trade is providing consular assistance to the family of an Australian reported missing in Cambodia,’ a department spokesperson told AAP on Monday.
The families of the missing men have filed an appeal with the UN Working Group on Enforced or Involuntary Disappearances.