German prosecutors are pursuing a Ukrainian man they allege was involved in the 2022 sabotage of the Nord Stream gas pipelines in the Baltic Sea. The case centers on explosions that damaged three of the four pipelines in September 2022, after which gas could no longer be transported through the routes.

Poland arrested the suspect, Volodymyr Z., acting on a European arrest warrant issued by Germany. Prosecutors said the man is a trained diver and part of a group accused of placing explosive devices on Nord Stream 1 and Nord Stream 2 near the island of Bornholm. German investigators allege the group hired a German yacht, sailed to the pipeline area, and planted explosives that caused multiple blasts.

Authorities say there is also suspicion involving other people connected to the alleged operation. While the investigation has focused on the perpetrators’ identities, broader questions about who ordered the attack remain disputed and have not been publicly established.

The case has diplomatic sensitivity because Germany and Ukraine have been aligned politically and militarily since Russia’s invasion of Ukraine in 2022, and because the alleged sabotage involves activity attributed to a Ukrainian cell. Germany’s legal efforts depend on extradition proceedings through the European arrest warrant system.