Ukrainian Former Officer Serhii K. Goes on Trial in Hamburg Over 2022 Nord Stream Pipeline Blasts

A former Ukrainian army officer identified under German privacy rules as Serhii K. appeared in court in Hamburg on 14 October 2026, charged with organizing the September 2022 explosions that damaged the Nord Stream gas pipelines.

The trial opened at the Hanseatic Higher Regional Court. Prosecutors allege that Serhii K., also named in extradition documents as Serhii Kuznetsov, led a group that included deep-sea divers, an explosives expert, and a boat captain. They say the team used a yacht rented in Rostock, entered German waters on a forged passport, and attached timer-controlled military-grade explosives to the pipelines at depths of roughly 70 to 80 meters near the Danish island of Bornholm. At least four devices, each weighing between 14 and 27 kilograms, detonated on 26 September 2022, rupturing three of the four pipelines and releasing large volumes of natural gas.

The charges include causing an explosion, damaging property, disrupting public services, and being an accomplice to a war crime by attacking civilian infrastructure. Prosecutors state that the operation was planned on behalf of unidentified Ukrainian state entities. Serhii K. denies any involvement. A second suspect remains in Croatia fighting extradition. Ukrainian authorities have consistently rejected any official role in the blasts.

Serhii K. was arrested in Italy in August 2025 while on holiday and extradited to Germany in November 2025. He has been held in pre-trial detention. Sixteen hearing dates are scheduled through mid-December, with further sessions expected into early 2027. Around 20 Ukrainian demonstrators gathered outside the courthouse on the opening day, calling for the defendant not to be convicted of war crimes.

The Nord Stream 1 and 2 pipelines were built to carry Russian natural gas directly to Germany under the Baltic Sea. Nord Stream 2 never entered commercial service after Germany suspended certification days before Russia’s full-scale invasion of Ukraine in February 2022. The explosions occurred seven months later, at a moment when European governments were already reducing Russian gas imports. Initial public speculation in the West focused on possible Russian involvement. German investigators later traced evidence to a group of Ukrainians.

The trial places a close ally of Ukraine in the position of prosecuting a Ukrainian citizen for an act that removed a major Russian energy export route. German officials have described the case as a matter of evidence and law rather than politics. The outcome will test how courts handle allegations of state-linked sabotage against critical infrastructure when the accused party is a wartime partner. Moscow has long demanded that the organizers be identified and has used the blasts in its narrative about Western actions against Russian interests.

The proceedings are the first public presentation of the full evidence assembled over four years. Witnesses, forensic details from the seabed, and records of the yacht’s movements are expected to form the core of the prosecution case. The defense will challenge the identification of the defendant as the organizer and the claim of Ukrainian state direction.