Swedish prosecutors said Wednesday they would drop their investigation into the September 2022 explosions on the underwater Nord Stream pipelines.

The cause of the blasts in the pipelines built to carry Russian natural gas to Germany is unknown, but it is widely believed that they were the result of an attack.

Public prosecutor Mats Ljungqvist said there was no Swedish jurisdiction in the case. 

The prosecution authority's investigation was "to establish whether Swedish citizens were involved in the act and whether Swedish territory was used to carry out the act, and thereby risked damaging Swedish interests or Sweden's security."

Since Sweden and Swedish interests were not targeted, "Swedish jurisdiction is thus lacking," he said.

Who blew up the Nord Stream pipeline?

Denmark and Germany are also examining the circumstances surrounding the blasts, and Sweden said it would hand evidence uncovered in their probe over to German investigators.

The investigation of the German Federal Public Prosecutor's Office was ongoing. "No further information will be provided at this time," a spokeswoman said.

Kremlin spokesman Dmitry Peskov described the closing of the Swedish probe as "a remarkable decision."

"Of course, now we need to see how Germany itself reacts to this, as a country that has lost a lot in relation to this terrorist attack," he said.

Copenhagen police, who are leading the Danish investigation, have said their investigation is not yet complete but an announcement is expected "within a short time."

The Nord Stream pipelines were already at the center of political tensions even before the blasts. Moscow cut natural gas supplies to Europe in suspected retaliation for sanctions against Russia's war in Ukraine.

Various theories have emerged outside of official investigations, with Ukraine, Russia, and the United States all being implicated. All have denied involvement.

lo/kb (AFP, AP, dpa, Reuters)