What? No investigation? This is pretty close to the top of the Wikipedia article on the matter:
The Swedish and Danish investigations were closed in February 2024 without identifying those responsible,[16][17] but the German investigation is still ongoing.[18] In August 2024 media reported that in June German authorities issued a European arrest warrant for a Ukrainian national suspected of having used the sailing yacht Andromeda together with two others to sabotage the Nord Stream pipeline.[19] As of June 2024 the suspect is still at large, having reportedly left the EU for Ukraine.[20]
The Swedish and Danish investigations were closed in February 2024 without identifying those responsible,[16][17] but the German investigation is still ongoing.[18] In August 2024 media reported that in June German authorities issued a European arrest warrant for a Ukrainian national suspected of having used the sailing yacht Andromeda together with two others to sabotage the Nord Stream pipeline.[19] As of June 2024 the suspect is still at large, having reportedly left the EU for Ukraine.[20]
https://en.wikipedia.org/wiki/Nord_Stream_pipelines_sabotage