Nord Stream: trial of Ukrainian suspect Serhii K. over the pipeline explosions opens in Hamburg

The trial of the Ukrainian man identified by German authorities as Serhii K. opened on October 14 at the Hanseatic Higher Regional Court in Hamburg (Hanseatisches Oberlandesgericht), over the explosions that destroyed three of the four Nord Stream pipelines in the Baltic, near Bornholm, on September 26, 2022. He is the first defendant to stand trial for the sabotage and denies the charges.

The German Federal Prosecutor’s Office charges him on four counts: a war crime by attacking non-military targets with military means, causing an explosion, destruction of structures and disruption of public utility services. The court, which is hearing the case in a state security panel, admitted the indictment and initially set 16 hearing dates through December 17, with more in January and February 2027.

The indictment

According to the prosecution, Serhii K. was at the time an officer of a special unit of the Ukrainian armed forces and worked with other Ukrainian soldiers. No later than September 8, 2022, he and six accomplices boarded the sailing yacht Andromeda, which had been chartered in the port of Wiek on Rügen. Divers placed four timed explosive charges on the pipelines, at depths of up to 80 metres.

In the indictment the prosecutors argue that the group acted “on the orders of Ukrainian state agencies,” while Volodymyr Zelensky has said that Ukraine had “nothing to do” with the explosions.

Serhii K. was arrested in late August 2025 at a resort on Italy’s Adriatic coast on a European arrest warrant and, after months of resisting extradition, was transferred to Germany on November 27, 2025. A second suspect, the Ukrainian Volodymyr Z., who according to the prosecution was one of the divers, was arrested in Pula, Croatia, and is contesting his extradition.

A case with political weight

The case is particularly sensitive for Germany, one of Kyiv’s closest allies. The Federal Court of Justice ruled in January 2025 that the case falls under German jurisdiction, as it concerns the country’s internal security.

In the first months after the explosions suspicion in the West turned toward Moscow, which had already used the price of natural gas as a lever of pressure, while Vladimir Putin accused the “Anglo-Saxons,” something the US and Britain denied. Denmark and Sweden closed their own investigations, and the German prosecutors found traces of underwater explosives in samples from the Andromeda.

The pipeline issue is also returning diplomatically, with Ukraine’s foreign minister criticising discussions in the US about restarting Nord Stream.