The Swedish Security Service said Friday that investigations into leaks detected in September in the Nord Stream gas pipeline in the Baltic Sea have found “explosive residue,” confirming the hypothesis that the pipeline had been subjected to sabotage.

“The Swedish Security Service is working intensively on the investigation regarding the detonations at the Nord Stream 1 and 2 pipelines. This investigation shows that the pipelines have been subject to gross sabotage,” the agency said in a statement. “In the crime scene investigations carried out on site in the Baltic Sea, the extensive damage to the gas pipelines resulting from detonations has been thoroughly documented. Several seizures have been made, including foreign items. The explosive residue was identified on a number of the seized and analyzed foreign items.”

“The Nord Stream incidents in the Baltic Sea are a very serious matter. Our Service is keeping a close eye on the development and taking the measures needed to fulfill its duty to protect Sweden and its security,” the agency added.

A series of explosions and subsequent underwater gas leaks occurred on the Nord Stream 1 and Nord Stream 2 natural gas pipelines on September 26.

Both pipeline pairs were built to transport natural gas from Russia to Germany through the Baltic Sea, and are majority owned by the Russian majority state-owned gas company, Gazprom.

The leaks happened as the Baltic Pipe was being opened for natural gas to come in from the North Sea through Denmark to Poland and were believed to have been caused by intentional sabotage; however, the perpetrators' identities and the motives behind such intentional sabotage have remained debated. (ILKHA)