Sweden's security service (SAPO) said Wednesday that it would investigate unexplained explosions and leaks on the Nord Stream pipelines in the Baltic Sea, calling them "aggravated sabotage."
SAPO was taking over the investigation from police because "it could relate to a serious crime that could at least in part be directed at Swedish interests," it said.
The intelligence agency added "it couldn't be ruled out that a foreign power is behind it".
In separate statements, SAPO and the Swedish Prosecution Authority said the investigation was currently being directed at potential "aggravated sabotage."
On Monday, leaks occurred in the Nord Stream 1 and Nord Stream 2 pipelines in the Baltic Sea off the coast of the Danish island of Bornholm.
Seismic institutes on Tuesday reported they had recorded "in all likelihood" explosions in the area prior to the leaks being detected.
Moscow and Washington both denied Wednesday that they were responsible for the suspected sabotage.
The EU has not named a potential perpetrator or suggested a reason for the suspected sabotage.
"Any deliberate disruption of European energy infrastructure is utterly unacceptable and will be met with a robust and united response," said EU foreign policy chief Josep Borrell on Wednesday.
The UN Security Council will convene on Friday at the request of Russia to discuss the damage. The French UN mission, which holds the presidency of the 15-member council for September, said the meeting would address the Nord Stream pipelines that Russia and European partners spent billions of dollars building.
Copenhagen police launch investigation
The Nord Stream 1 and 2 pipelines have been at the centre of geopolitical tensions in recent months as Russia cut gas supplies to Europe in suspected retaliation against Western sanctions following Moscow's invasion of Ukraine.
While the pipelines – operated by a consortium majority-owned by Russian gas giant Gazprom – are not currently in operation, they both still contain gas.
According to Danish authorities, the leaks will continue until the gas in the pipelines is exhausted, which is expected to occur on Sunday.
More than half the gas in the damaged Nord Stream 1 and Nord Stream 2 gas pipelines has left the pipes, according to Danish Energy Agency head Kristoffer Böttzauw.
Danish police have also launched an investigation into the matter and was cooperating with police authorities in Sweden and Germany, Copenhagen police chief Anne Tonnes told a press briefing.
The pipelines contained a total of 778 million cubic meters of natural gas, which corresponds to 32% of Denmark's annual CO2 equivalent emissions, the Energy Agency said in a statement.
Germany says must brace for 'unimaginable' after gas leaks
Germany's interior minister said Wednesday the country must prepare for previously "unimaginable" threats to its energy security after dramatic pipeline leaks the EU blamed on sabotage.
Nancy Faeser said Europe's top economy would need to enhance its vigilance to address such risks in the wake of the damage to the Nord Stream 1 and 2 energy links between Germany and Russia.
"We have to adapt to scenarios that were previously unimaginable," she said. "That requires strong security authorities with the necessary resources and powers."
Faeser called for a rapid probe of the "probable act of sabotage" on the pipelines beneath the Baltic Sea close to Denmark and Sweden so that "those responsible" can be identified.
"Protecting critical infrastructure has top priority," she said, adding that Berlin had presumed "for months" that there was an "abstract threat to energy infrastructure" given its high profile in the wake of Russia's war on Ukraine.
Defense Minister Christine Lambrecht said the "troubling incident" underlined the importance of an ongoing "modernization" of the German navy's fleet for surveillance in cooperation with partner states on the Baltic.
Germany, which until recently was highly dependent on Russia energy, will wait for a full investigation of the incident before drawing conclusions, a government spokesman said on Wednesday.
(FRANCE 24 with AFP, AP and Reuters)