Damage to the Nord Stream (NS) pipeline systems that connected Russian natural gas supply to Western Europe was caused by detonations and more than likely sabotage, authorities with the Swedish Security Service said Thursday.

Sweden’s counter-espionage and counter-terrorism officials disclosed some of the first official conclusions into the incident since gas leaks in the Baltic Sea were detected in late September.

“The crime scene investigation has shown that there have been detonations near Nord Stream 1 and 2, within the Swedish economic zone, resulting in extensive damage to the gas pipelines,” Security Service officials said.

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