BERLIN (Reuters) - German federal prosecutors on Thursday took over an investigation into the alleged kidnapping last month of a Vietnamese businessman and his companion, citing new evidence that the two were likely to have been taken to the Vietnamese embassy in Berlin before going back to Vietnam.

The chief federal prosecutor’s office said the investigation was focused on the suspicion of foreign intelligence activity and the unlawful deprivation of liberty.

The probe had previously been under the control of state prosecutors in Berlin.

The German authorities say Vietnam has now withdrawn an extradition request for Trinh Xuan Thanh, who had been seeking asylum in Germany but is wanted in the southeast Asian country on charges of financial mismanagement that caused losses of around $150 million.

Germany on Thursday said it was considering what steps to take after Vietnam failed to honor its demand for his return.

Evidence showed that Thanh and an unidentified woman were dragged into a vehicle on a street in Berlin on Sunday, July 23, prosecutors said in a statement.

“Given the investigation thus far, it is assumed that the victims were taken to the Vietnamese embassy in Berlin, and from there to Vietnam,” it said.

“Against that backdrop, the federal prosecutor’s office has taken over the investigation,” it added.

Germany’s foreign ministry last week accused Vietnam of abducting Thanh, in a scene reminiscent of Cold War disappearances in the then-divided German capital.

This week, the Germans said they were considering their next steps, noting that Vietnam receives a considerable amount of development aid from Germany.

In 2015, Germany committed 220 million euros ($257.80 million) in such aid to Vietnam over two years.

Germany is Vietnam’s biggest trading partner in the European Union, whose members are due to consider approving a free trade agreement with Hanoi.

Thanh had been an executive at state oil company PetroVietnam and became a focus of attention in 2016 when he was found with a luxury Lexus car with a government registration plate.

The businessman appeared on Vietnamese state television last week but it was unclear if he was speaking freely when he said: “I wasn’t thinking maturely and decided to hide and during that time I realized I need to return to face the truth and ... admit my faults and apologize.”

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