[11][12] The leaks occurred one day before Poland and Norway opened the Baltic Pipe running through Denmark, bringing in gas from the North Sea, rather than from Russia as the Nord Stream pipelines do.

[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.

[42][45][47] After Germany's initial report of pressure loss in Nord Stream 2, a gas leak from the pipeline was discovered by a Danish F-16 interceptor response unit 25 kilometres (16 mi) southeast of Dueodde, Bornholm.

[50] Citing danger to shipping, Danish Maritime Authority closed the sea for all vessels in a 5-nautical-mile (9.3 km; 5.8 mi) zone around the leak site, and advised planes to stay at least 1,000 m (3,300 ft) above it.

[62] The Swedish public service broadcaster SVT reported that measuring stations in both Sweden and Denmark recorded strong underwater explosions near the Nord Stream pipelines.

[63] On 30 September 2022, Denmark and Sweden jointly submitted a letter to the United Nations Security Council stating that the leaks were caused by at least two detonations with "several hundred kilos" of explosives.

[68] On 21 June 2023, underwater drone footage obtained in a collaboration between German RTL, French Libération, Danish Ekstra Bladet and TV 2 from the southernmost sabotage site was published along with an analysis.

A named demolitions expert formerly with Denmark's Engineer Regiment and with the Danish Defence Intelligence Service argued that the steel was cut with a shaped charge using just a few kilograms of high detonation velocity explosives.

[79] On 18 October, the Swedish newspaper Expressen released photos it had commissioned of the Nord Stream 1 damage, showing at least 50 metres (160 ft) of pipe missing from its trench, as well as steel debris around the site.

The German government claimed that no on-site investigation had taken place yet, and refused to disclose information about the presence of NATO or Russian ships near Bornholm on the day of the presumed sabotage, citing state secret.

[89] On 2 June 2023, German police conducted a search of a flat near the Polish border and interviewed a woman whose 26-year-old male partner, a Ukrainian national who has returned to Ukraine, was named as a suspect in the investigation.

– discuss] In August 2024 media reported that in June German authorities issued a European arrest warrant for a Ukrainian national living near Warsaw suspected of having used the yacht Andromeda together with two others to sabotage the Nord Stream pipeline.

[96] Der Spiegel reported that seven days after the Federal Prosecutor General had sent his arrest warrant to Poland, the suspect reached Ukraine in a vehicle with diplomatic plates, used by the Ukrainian embassy in Warsaw.

[97][98][99][100] The Wall Street Journal subsequently reported both that the German authorities denied making the procedural error and that the Polish Internal Security Agency was tasked with handling the arrest but did not execute the warrant.

[101] On 6 June 2023, The Washington Post reported that an intelligence agency of an unnamed European "close ally" had notified the CIA of a Ukrainian military plan for a covert attack on the pipeline.

Analysis of satellite imagery and AIS-data indicate that the following day SS-750 was operating in the area together with five other Russian naval vessels including the rescue tugs SB-123 and Alexander Frolov that are capable of lowering into the sea objects weighing hundreds of kilograms such as mines and other explosive devices.

[93] In August 2023, Der Spiegel claimed that German investigators tend to believe that the Russian Navy was near the pipeline in the days before the attack because they wanted to patrol it for protection, as Russia may have received information, as did the CIA and Dutch intelligence, on a possible sabotage plan.

[123] In April 2023, German Defense Minister Boris Pistorius cautioned against making premature accusations as to whom was behind the attack, suggesting that the alleged Ukrainian use of the 50-foot-sailing Yacht Andromeda might be a false flag operation.

[125] In September 2023, Andreas Umland, analyst at the Stockholm Centre for Eastern European Studies, argued that the Andromeda was most likely a false flag created by Russia to implicate Ukraine.

[144] In October 2024, the Swiss newspaper Die Weltwoche wrote an article based on an interview given to Danish Politiken by the Christiansø port harbourmaster on the second anniversary of the Nord Stream pipelines sabotage.

[146] In March 2023, several international media outlets, citing anonymous sources, reported that a pro-Ukrainian group may have carried out the attack[147][148][149] using the Andromeda, a 15.4-metre (50.6 ft) Cruiser 50 sailing yacht from Bavaria Yachtbau.

The yacht is said have left Rostock on 6 September, briefly mooring at the port of Wiek and at the Danish island Christiansø, which is located 12 nautical miles (22 kilometres) from the explosion site.

[151] The Danish and the Norwegian engineering newspapers Ingeniøren and Teknisk Ukeblad cited lieutenant commander J. Riber, this time for several reasons why it is not credible that such a small vessel was used for the sabotage.

A senior official of the Security Service of Ukraine also denied his government's involvement and reiterated that Zelensky did not approve the implementation of any such actions on the territory of third countries and did not issue relevant orders.

[156] According to a European lawmaker briefed in late 2022 last year by his country's main foreign intelligence service, investigators had been gathering information about an estimated 45 "ghost ships" whose location transponders were not on or were not working when they passed through the area, possibly to cloak their movements.

[189] In late 2022 August Hanning who until 2005 headed Germany's Federal Intelligence Service, said that Russia, Ukraine, Poland and Britain had a plausible interest in disabling the pipelines, as well as the US.

[192] In a widely shared post on Twitter, Polish MEP and former foreign affairs and defence minister Radek Sikorski stated simply, "Thank you, USA", next to a photo of bubbling water above the pipeline damage.

[193] Hours later he followed up with a tweet that Ukraine and the Baltic states had opposed Nord Stream's construction for 20 years and tagged Russia's Ministry of Foreign Affairs: "Someone, @MFA_Russia, did a special maintenance operation.

[73] A day after the attack, adviser to Ukraine's President Zelenskyy Mykhailo Podolyak blamed Russia,[204] alleging their intent "to destabilize economic situation in Europe and cause pre-winter panic.

"[208][209] The following day EU's foreign policy chief Josep Borrell said: "Any deliberate disruption of European energy infrastructure is utterly unacceptable and will be met with a robust and united response".