As her daughters and sisters watched, Tran Thi Hien, a 47-year old British citizen of Vietnamese origin, first denied but finally admitted being a member of a drug trafficking ring that bought and distributed more than 50 kilograms of heroin across Vietnam and South-East Asia.

Two of Hien’s daughters, who travelled from London to attend their mother’s trial, expressed outrage at the charges and condemned the harsh conditions under which she has been held.

Unless the Vietnamese judges are uncharacteristically lenient, Ms Hien will be sentenced to death by firing squad — the recommended sentence for smuggling more than 600g of heroin.

Hien appeared in the Quang Binh provincial court in the sleepy seaside town of Hong Doi after two and a half years in custody, during which she has spent just ten minutes with a member of her British family.

The lawyer who represented her had only four days to prepare her case. Her original lawyer, who had been working on her defence for a year, was prevented from attending the trial by secret police who incarcerated her in her home.

Hien, a restaurant owner from South London, began by denying her part in the case, but broke down after repeated interrogation by members of a five-judge panel and two uniformed prosecutors. Her own lawyer cross-examined her for ten minutes.

“I’m 100 per cent sure she’s not involved,” said Hien’s daughter, Tina Tran, 24, who flew to Vietnam with her sister, Jenny. “She’s been here two years and they haven’t told us a single thing about what’s going on, and she’s not allowed visitors. We don’t know who to talk to, and they won’t tell us anything here.”

Hien left Vietnam in the early 1980s as one of the “boat people” — refugees who made the perilous sea crossing to Hong Kong. Her family insist that when she was arrested in June 2004 she was simply on holiday, visiting relatives and the grave of her mother.

But the Vietnamese prosecutors tell a different story. The case, set out in painstaking detail in a 33-page indictment, was read out over 90 minutes yesterday. It accused Hien and seven co-defendants of operating a massive smuggling operation that transported heroin out of Laos to be sold throughout Vietnam, Hong Kong and China.

Hien is accused of making payments, of as much as $200,000, for four separate deliveries containing 120kg of heroin that were concealed in trucks containing motorcycle parts. As well as six Vietnamese defendants, another British citizen, Le Manh Luong, is accused of drug trafficking, gun-running and forging documents.

Despite it being an open trial, several relatives of the accused were not allowed into the court. The Times was removed from the court during Hien’s cross-examination.

She looked confused and anxious, and on the few occasions when she attempted to speak to her daughters she was silenced by the two female police officers who flanked her.

Hien was barely audible as she stood for an hour at the wooden witness stand. “Are the accusations correct?” the chief judge asked repeatedly. “If you don’t deny it, then [that means] you agree.”

Hien first denied involvement in all but one of the four smuggling operations detailed in the indictment, which involved the transport of 16kg of heroin.

“I was in Hong Kong [at the time of one operation],” she said, but shortly contradicted herself by saying that she had been in Laos.

“Is that true? Is it true?” the judge repeated. One prosecutor said: “Remember that telling the truth will be to your advantage when the court makes its decision.”

Eventually she admitted that she had knowingly taken part in the trafficking of deliveries of 10kg and 26kg loads of heroin.

She admitted paying cash for a 70kg shipment at the behest of her lover, Mr Luong, but insisted that she did not know it was for drugs.

Death sentence is a routine ruling

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