The trial has begun in Berlin of a member of the kidnap gang allegedly sent by the Vietnamese government to Germany last summer to seize a fugitive official.
Prosecutors are presenting evidence of a Cold War style intelligence operation to pluck the wanted man from the streets of Berlin and spirit him back to Hanoi.
A Vietnamese-Czech man, identified in court papers as Long N H, stands accused of renting the van used in the abduction of Trinh Xuan Thanh and his mistress.
Prosecutors believe that the operation was overseen by a top official in Vietnamese intelligence and carried out in broad daylight by a team of Vietnamese agents.
Only the man ordered to hire and deliver the vehicles, Long, was left behind to face German justice. Prosecutors have said they are also investigating the role of the deputy head of Vietnamese intelligence.
The trial will be deeply embarrassing for the Vietnamese government, which has denied all involvement in the abduction. The government still insists that Thanh, once the head of a state construction company, returned to Vietnam voluntarily to face corruption charges.
The case has already severely damaged relations between the two countries and threatens to derail ratification of the free trade agreement between the European Union and Vietnam.
German newspapers report that Vietnamese secret agents tracked Thanh’s mistress on a visit from Paris, enabling them to uncover Thanh’s secret hideout in Berlin.
Long is alleged to have hired a BMW vehicle to carry out the surveillance operation and the VW van used in the abduction.
Witnesses had called the police on a sunny Sunday morning last July to reply that a couple walking in the Tiergarten Park were being violently forced into the vehicle by a squad of determined assailants.
The two were then allegedly driven to the Vietnamese embassy before being taken out of the country and flown to Hanoi, where Thanh appeared on state television a week later saying that he had returned voluntarily.
German police are reported to have tracked every movement of the vehicles and all the phone calls made by agents involved in the operation.
The presentation of forensic evidence in a court of law will prove extremely uncomfortable for the Vietnamese government, which has contented itself so far with bland denials of any involvement.
The credibility of General-Secretary of the Vietnamese Communist party, Nguyen Phu Trong, is personally on the line.
Before Thanh’s arrest, he had told constituents that the authorities would do everything necessary to bring the fugitive to justice.
Trong has led a wide-ranging anti-corruption campaign targeting former senior officials and bankers, of which Thanh’s arrest and conviction has been the most spectacular so far.
Thanh was sentenced to life imprisonment on charges of corruption and economic mismanagement earlier this year.