German police raided a house in a town near Berlin in connection with the sabotage of the Nord Stream gas pipeline last September.
Detectives from the German Federal Crime Agency searched an apartment in the city of Frankfurt (Oder) on May 25.
The apartment belongs to a young woman who was romantically involved with a prime suspect with whom she has a child, according to a report by Süddeutsche Zeitung.
Detectives have taken a DNA sample from the child which they will now compare with DNA found on a yacht that the saboteurs allegedly used during the sabotage operation.
The woman, who is not a suspect herself, is said to have cooperated with police and handed over her mobile phone.
German media claim to know the identity of the woman’s former partner, who is a serving soldier in the Ukrainian army.
German investigators believe he was part of a crew of six who hired a charter yacht on the German Baltic coast and sailed to the Nord Stream pipelines where divers planted explosives on the outer casing of the pipeline.
The boat was rented through a Warsaw-based front company claiming to be a travel agency, German media reported.
The woman named owner of the company is a Ukrainian who lives in Ukraine.
On September 26 last year, an explosion punctured three of Nord Stream 1 and 2’s four pipelines, which were built to transport gas directly from Russia to Germany.
While various media have traced the culprits to Ukraine, Germany’s top spy warned against jumping to conclusions.
Speaking in Berlin last month, Bruno Kahl, head of the Federal Intelligence Service, said there are “clues that lead in all sorts of directions”.
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