✧. Executive summary — short: On 26 September 2022, powerful underwater blasts ruptured three of the four Nord Stream pipelines in the Baltic Sea, producing major methane leaks and leaving one of Europe’s most sensitive energy infrastructures disabled. National inquiries (Sweden, Denmark, Germany) produced forensic leads — including traces of subsea explosives linked to a chartered yacht — but produced different outcomes: Sweden and Denmark later closed their criminal probes (citing insufficient grounds for charges), while Germany continued its investigation and has linked the sabotage to a team that may have operated from a yacht called Andromeda. In August 2025, Italian police detained a Ukrainian national on a German arrest warrant; extradition is being processed, and the case remains fluid. Moscow — represented recently at the UN by Dmitry Polyanskiy — accuses Western investigators of excluding Russia, calls the blasts “an act of international terrorism,” and demands an international probe. The factual record is partial; the political and legal stakes are high.
✦. Quick chronology (core facts you must keep in view)
26 September 2022 — Multiple underwater explosions near the Danish island of Bornholm damaged Nord Stream 1 and Nord Stream 2 pipelines, causing large methane leaks into the Baltic.
Late 2022–2024 — National investigations launched by Sweden, Denmark, and Germany. Forensic teams collected seabed samples and examined maritime traffic. In mid-2023, Germany told the UN it had found traces of subsea explosives in samples taken from a yacht it had searched.
Feb 2024 — Denmark announced it had closed its investigation, concluding sabotage but saying there were insufficient grounds to open a criminal case; Sweden likewise wound down its probe and transferred material to Germany. Germany remained the active investigating jurisdiction.
2023–2024 (reporting) — Investigative media (Der Spiegel, WSJ, others) published detailed reconstructions alleging a small team — two divers and supporting crew — may have used a rented yacht to approach the sites and deploy charges; German authorities issued arrest warrants in 2024 for suspects believed connected to the yacht and the operation. These reports remain contested and politically sensitive.
21 August 2025 — Italian police detained a Ukrainian national suspected by German prosecutors of coordinating the sabotage; Germany issued a European arrest warrant and expects to move toward extradition and judicial proceedings. This is the first public arrest linked by prosecutors to the 2022 sabotage.
✦. The evidence base — what investigators say, and its limits
Forensics & physical evidence. Multiple investigators reported that explosives caused the damage and that samples taken at the damage sites and from a chartered yacht (the Andromeda) contained traces consistent with subsea explosives. Germany told the UN in 2023 that traces of the same explosives were found in samples taken from a yacht that may have been used to transport charges. That forensic link — while significant — does not by itself prove who ordered or directed the operation.
Maritime and acoustic data. Investigators examined AIS (Automatic Identification System) tracks, satellite imagery, and acoustic/seismic signatures. Some reconstructions place a chartered sailboat in the area in the days around the sabotage; media reconstructions and leaked documents have suggested a coordinated small-team operation. However, intelligence and evidence sharing across states has been partial, and many investigative files remain classified or subject to prosecutorial secrecy.
Investigative outcomes to date. Denmark and Sweden concluded that sabotage had occurred but closed criminal probes for lack of sufficient prosecutable evidence; Germany kept investigating and has publicly asserted stronger forensic leads, culminating in arrest warrants and, most recently, the 2025 detention in Italy. None of the national processes has yet produced an internationally prosecuted case that conclusively names, convicts, or fully explains a state actor behind the attack.
✦. Technical feasibility: could “amateur divers” do this at ~70–80 m?
Dmitry Polyanskiy’s dismissive comment — that “only a child or a very naive person can believe that three amateur divers could execute the operation at 80 metres in NATO-monitored waters” — is rhetorically powerful and worth testing against technical reality.
Depth and human diving limits. Recreational scuba is normally limited to ~40 m. Operations at 70–80 m enter the realm of technical diving or professional (military/commercial) diving, which requires mixed breathing gases (helium blends), rebreathers, staged decompression schedules, and significant training. Unsophisticated “amateur” recreational divers rarely operate safely at those depths.
What professionals and special operators can do. Armed forces EOD/combat divers and highly trained technical teams routinely perform missions at 70–90 m using closed-circuit rebreathers or surface-supplied systems, and conduct long decompression profiles. Saturation diving infrastructure or specialized apparatus is often used for repetitive or longer-duration tasks at depth. These are complex, logistic-heavy undertakings.
ROVs and robotics. Remotely operated vehicles (ROVs) and mine-disposal vehicles can inspect, manipulate, and even place or neutralize devices at depths far greater than 80 m — and they can be deployed from modest craft if equipped and crewed properly. That both increases plausible technical means (human divers are not the only option) and complicates attribution.
Bottom line on feasibility: what Polyanskiy calls “amateur” is highly unlikely; the operation as reconstructed by investigators would require either (a) highly trained divers, (b) specialist commercial/saturation diving support, (c) sophisticated rebreathers and multiple staged decompressions, or (d) ROVs/mining EOD robots. Thus, if the attack was carried out by divers at 70–80 m, they were most likely professional or former military personnel with specialized equipment — not casual recreational divers. The forensic claim that traces were found on a yacht, and the investigators’ conclusion that trained divers could have attached devices, aligns with that technical assessment — but it does not establish which government (if any) directed the operation.
✦. Intelligence, responsibility, and contested narratives
Since the event, multiple narratives have competed:
Russian insistence on Western culpability / “international terrorism.” Moscow has repeatedly accused Western states of responsibility or cover-ups, and Russian envoys have demanded an international inquiry, arguing Russia was excluded from national investigations and therefore cannot trust those findings. Dmitry Polyanskiy has framed exclusion as evidence of politicization and of a larger security threat. Russia’s framing is politically potent but must be evaluated against what independent forensic evidence supports and against Russia’s own strategic interest in shifting blame.
German prosecutorial line (pro-Ukrainian team). German investigators — supported by media reconstructions like those in Der Spiegel and reporting by major outlets — have alleged that a small pro-Ukrainian group attacked a chartered yacht; leaked reporting has described an operation of divers and supporting crew. Germany has produced arrest warrants and, in 2025, a first arrest (Italy). These claims are significant but politically explosive; Ukraine denies state responsibility, and some reporting suggests operations may have been initiated at sub-state or military-rogue levels.
Conspiracy and alternative theories. Other narratives (from Russian state media to assorted commentators) point fingers at the U.S., NATO, or even non-state actors. Many of these claims rely on selective leaks, politicized intelligence, or speculation; independent forensic consensus remains the anchor for legal accountability.
Assessment: the balance of publicly available forensic and investigative reporting (forensic traces on a yacht, maritime movement records, and prosecutorial actions) has pushed investigators toward a specific group hypothesis — but the full chain of command, motive, and whether a state authorized the act remains either unproven or in internal classified files. That ambiguity fuels the competing narratives and Russia’s demand for an international, independent review.
✦. Why Russia raises “exclusion” and what an international probe would mean
Russia’s diplomatic line — that it was excluded from national investigations and therefore seeks an international probe — has two overlapping components:
➊. Procedural grievance: Russia argues that a crime affecting its national infrastructure should allow it a role in cross-border investigations. In practice, criminal jurisdictions (Denmark, Sweden, Germany) have domestic prosecutorial responsibilities, and intelligence-sharing between states can be constrained by evidentiary chains, classified sources, and legal strategy. Nations sometimes restrict sharing sensitive material for national security reasons; that can produce diplomatic complaints even when investigators believe they are following proper legal processes.
➋. Political signaling: Calling the attack “international terrorism” and pressing for a UN or international inquiry reframes the incident as a global security threat and pressures Western governments politically. Whether such a probe would produce more clarity depends on (a) whether states agree on a mandate, (b) what classified intelligence they are willing to share, and (c) whether the inquiry would be truly independent or become another arena for geopolitical contestation.
Practicality of an international probe: An effective independent probe would need judicially-safeguarded access to forensic material, raw intelligence (signals, maritime tracking, satellite imagery), the ability to subpoena or compel testimony, and guarantees about evidence handling. Those conditions are politically and legally difficult to satisfy, especially when national investigators assert prosecutorial primacy. Nonetheless, a carefully designed, technically capable multilateral forensic commission could add value — if major players (EU states, NATO members, possibly neutral parties) agree on an evidence-handling protocol.
✦. Legal and geopolitical consequences (if prosecutions proceed)
Extradition & domestic trials. The Italian detention and an expected extradition to Germany could produce the first public trial. That would be the first time a court publicly tests the chain of evidence tying suspects to the sabotage. The outcome depends on admissible forensic links (explosive residue, DNA, AIS/satellite tracks, witness testimony).
State responsibility vs. sub-state violence. Even if individuals are convicted, proving a sponsoring state’s role (command responsibility, approval, or tacit consent) is far harder. International law distinguishes acts by private actors from state action; proving state authorship requires direct links (orders, logistical support, communication intercepts) that are often classified and politically explosive.
Escalation & precedent. Attacks on undersea civilian infrastructure — pipelines, cables — raise huge risks: they can escalate interstate tensions, threaten civilian commerce and climate (huge methane release), and create a precedent for covert strikes on critical infrastructure. How states respond (criminal prosecution, diplomatic pressure, sanctions, or military posture changes) will shape norms about undersea security.
✦. Policy recommendations (what an ideal, stabilizing response would include)
➊. Independent technical commission: Convene a tightly defined, multilateral forensic commission of neutral technical experts (marine engineers, seismologists, explosives forensics) with secure channels to national evidence stores — designed to complement, not usurp, criminal prosecutions.
➋. Secure intelligence-sharing protocols: Create legal mechanisms to allow prosecutors to access classified intelligence under judicial secrecy (so states can contribute sensitive material without public exposure).
➌. Protect undersea infrastructure: Accelerate investment in monitoring (ROVs, acoustic arrays), legal protections, and multinational early-warning architectures for critical subsea infrastructure.
✦. Conclusion — what to watch for next
Extradition and pre-trial hearings in Germany after the Italian detention (watch public court filings and prosecutor statements).
Any declassification or intergovernmental intelligence sharing that clarifies whether a state sponsored, authorized, or merely tolerated the operation.
UN or ad hoc international forensic steps: whether states will agree to a neutral, technical commission, and whether such a body would have access to the forensic material national prosecutors currently hold.
For readers and policymakers, the Nord Stream sabotage is now both a criminal investigation and an international rule-of-law test: forensic science and careful, transparent legal process must carry the day if the episode is to be resolved without deepening international divisions. Russia’s charge — that it was excluded — is a diplomatic fact that cannot be ignored; whether its framing is persuasive depends on whether independent, mutually trusted forensic processes can be established. Until that happens, contested narratives and geopolitics will continue to shape how the world reads the seabed.
Written by
Eelaththu Nilavan
Military and Global Political Strategy Analyst
28/08/2025
The views expressed in this article are the author’s own and do not necessarily reflect Amizhthu’s editorial stance.
