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Sweden finds explosive traces at Nord Stream blast sites, confirms sabotage

One of four leaks at one of the damaged Nord Stream natural gas pipelines in the Baltic Sea, as seen on Sept. 29. (Danish Defense/AFP/Getty Images)

BRUSSELS — The mysterious blasts in September that made the largest-capacity natural gas pipelines from Russia to Europe inoperable were caused by “gross sabotage,” Swedish authorities confirmed Friday, noting that traces of explosives have been found as part of the ongoing investigation.

Prosecutor Mats Ljungqvist and the Swedish Security Service reported that their examination of the Nord Stream 1 and 2 pipelines in the Baltic Sea has documented “extensive damage” and revealed several “foreign items” — some with detectable “explosive residue.”

But the statements did not address the key questions of the months-old mystery: Who is responsible? And how did they go about it?

European leaders blame Russian ‘sabotage’ after Nord Stream explosions

“The advanced analysis work is still in progress — the aim is to draw more definitive conclusions about the Nord Stream incidents,” the Security Service statement said. “The investigation is extensive and complex and will eventually show whether anyone can be suspected of, and later prosecuted for this.”

The blasts occurred south of the Swedish mainland, east of the Danish island of Bornholm. Multiple investigations are underway, with Danish and German authorities also collecting evidence.

European officials began using the term “sabotage” within hours of the simultaneous blasts in late September. Seismologists said the data pointed to explosions, not naturally occurring earthquakes or landslides.

“These are deliberate actions, not an accident,” Danish Prime Minister Mette Frederiksen told reporters on Sept. 27. “The situation is as serious as it gets.”

European leaders pointed to Russia as the only actor with the technical capability and motivation to damage the Nord Stream pipelines with underwater explosions.

The damage did not have an immediate impact on Europe’s energy supplies. Russia had already cut off gas flows as relations deteriorated amid the war in Ukraine. And countries previously dependent on Russian gas had already scrambled to build up stockpiles and secure alternative energy suppliers.

But European leaders suggested the explosions were intended as a threat, sending a message that their critical infrastructure could be vulnerable if they continued their support of Ukraine. They have since tightened security around key infrastructure and boosted naval operations.

Russia has denied responsibility and questioned the logic of the European account. The Russian prosecutor general’s office has launched legal proceedings for an act of international terrorism.

Nord Stream spill could be biggest methane leak ever but not catastrophic

Russian energy giant Gazprom stopped the gas flow through Nord Stream 1 earlier this year, citing technical problems, while European leaders accused Moscow of “blackmail.” The newer Nord Stream 2 pipeline was not yet approved for operation; Germany froze the project in the lead-up to the war in Ukraine.

The explosions hit both pipelines — and the resulting leaks produced the largest-ever single release of methane gas into the atmosphere. But energy and climate experts did not anticipate it would have a significant effect on climate change.

Francis reported from London.

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