Swedish investigators are looking into the movements of a Chinese vessel in the Baltic Sea after two internet cables were severed in what some Western leaders suspect was an act of sabotage.

European officials are looking toward Russia after two submarine internet cables in the Baltic Sea were suddenly disrupted in an apparent sabotage operation, just weeks after the United States warned that Moscow was likely to target critical undersea infrastructure.

Germany’s defense minister said damage to two fiber-optic cables on the sea floor appeared deliberate, but a culprit was not known.