As recent as November 2023, the powers to be claim Ukraine special ops (not Russia) blew up the pipeline. No one believes they carried it out alone. That leaves their backers, the same ones Sweden wants to join.
https://www.washingtonpost.com/national-security/2023/11/11/nordstream-bombing-ukraine-chervinsky/
Yup, there’s lots of claims and accusations floating around
But very little actual evidence