Human rights groups are urging the federal government to ratchet up pressure on Vietnam over the fate of an Australian pro-democracy campaigner who is languishing in jail after disappearing in Cambodia last month.
Melbourne man Hiep Tran vanished after travelling to the region in September to meet Vietnamese human rights groups in Cambodia.
More than a week later, Vietnam's Ministry of Public Security said it had caught Mr Tran and another human rights activist, Norwegian citizen Duc Thuan Nguyen, trying to illegally enter Vietnam to engage in "terrorist and sabotage activities".
But that has been furiously denied by Hiep Tran's supporters, who say the two men had no plan to enter Vietnam, and who allege they were likely abducted by Vietnamese authorities and bundled across the border.
Human rights groups have also pointed out that the two men missed other scheduled appointments in Cambodia and left their luggage and personal items in their hotel rooms in Cambodia — suggesting they had no plans to leave the country.
Mr Tran (left) and Duc Thuan Nguyen travelled to Phnom Penh to meet Vietnamese human rights activists. (Supplied)
The two men are members of Viet Tan, an overseas Vietnamese opposition group that the country's ruling party has labelled a terrorist organisation.
Most scholars say that while Viet Tan has roots in armed anti-Communist groups that emerged in the aftermath of the Vietnam War, it relaunched in the 2000s as a political party committed to peaceful change.
Arrest 'outrageous and unacceptable'
Human rights advocate Phil Robertson told the ABC that Hiep Tran's arrest was "outrageous and unacceptable" and another sign that Vietnamese authorities were increasingly determined to target political opponents overseas under its powerful president, former security chief To Lam.
"To Lam has made a point of going after vocal critics whenever he can, and that has included abductions in Thailand, abductions in Germany, abductions now in Cambodia," he said.
Oslo-based lawyers for Duc Thuan Nguyen called his disappearance a "textbook case of enforced disappearance, within a framework of Vietnamese transnational repression".
Cambodia has denied handing over the men to Vietnam, saying they were intercepted at the border crossing.
Vietnam's government has denied targeting critics overseas, saying those allegedly abducted in Thailand were trying to cross illegally back into Vietnam, while the Vietnamese citizen who disappeared in Germany actually returned home voluntarily.
Government making representations
Last week, Foreign Minister Penny Wong told the ABC she would deal with the matter carefully in public.
"I can confirm I'm aware of this case and that Australian officials are aware," she said.
"I can confirm that we have made representations, including from me, in relation to this matter.
"But I'm not in the position, because of privacy considerations, to give you any more information than that."
Mr Tran's supporters say he is currently being detained in the notorious B34 detention centre in Ho Chi Minh City, where political prisoners are often held before trial.
Hiep Tran is a pro-democracy campaigner. (Supplied)
Australian officials had not yet been granted consular access to him as of Monday this week — although it was not clear if that has changed in recent days.
His wife, Chloe Dang, said she was "heartbroken" to be separated from her husband, and has pleaded with Vietnam to set him free.
Hiep Tran is not the first Australian member of Viet Tan to be targeted by authorities in Vietnam — Sydney man Chau Van Kham was released in 2023 after Prime Minister Anthony Albanese and other Australian government ministers lobbied the government to free him.
Mr Robertson said Australia should be "quite bold" and "be prepared to really push hard, both privately and publicly, for Hiep Tran's release".
"Otherwise, we're going to have him facing, you know, a kangaroo court trial and a long prison sentence, that is going to cause major problems for his family and for Vietnamese Australian relations," he said.
'I've been crying a lot'
The case has also stirred debate in the Vietnamese community in Australia, which includes both government supporters and opponents of the communist ruling party.
My Linh Do says she was interrogated for five days after being detained at the Vietnamese border in 2012. (Supplied)
Brisbane-based community activist My Linh Do, who is a prominent pro-democracy advocate and critic of Vietnam's ruling party, said Hiep Tran's experience reminded her of her own confrontation with Vietnamese authorities almost 15 years ago.
"Since Hiep Tran's incident last week, I got very scared, and I have been losing sleep," she told the ABC.
"I haven't been able to eat. I've been crying a lot."
My Linh told the ABC she was detained in 2012 at the Vietnamese border and interrogated for five days before being released.
My Linh Do says Hiep Tran's arrest reminded her of her own traumatic incident. (Supplied)
She said authorities intimidated her, tried to access her Queensland state government email account and even tried to recruit her to provide intelligence back to the Vietnamese government.
"They didn't use the term 'work as a spy', but they said they want me to report any suspicious activity by a Vietnamese in Australia who is involved in anything," she told the ABC.
DFAT officials 'continue to engage'
A spokesperson for the Department of Foreign Affairs and Trade (DFAT) did not say if they had been granted consular access to Mr Tran.
"Australian officials in Vietnam continue to engage with the Vietnamese government," they said.
DFAT's official travel advice for Vietnam warns that people can be detained for "perceived involvement with non-state-sanctioned political organisations or groups perceived by the Government of Vietnam to be associated with dissident groups".
Allegations 'unfounded and misleading'
Vietnam's embassy in Canberra told the ABC that the allegations of forced abduction were "unfounded and misleading."
"In Viet Nam, arrests and prosecutions are carried out in accordance with the law, as in other countries," a spokesperson said in a statement.
The spokesperson also denied that Vietnamese Australians were treated inappropriately when travelling to the country.
"The steady growth in Australian visitors to Viet Nam, reaching a record half a million last year — including thousands of Australians of Vietnamese origin — reflects Viet Nam's appeal as a travel destination and the growing people-to-people ties between our two countries," they told the ABC.
Cambodia's embassy in Canberra did not respond to the ABC's questions.