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.

Two data cables running along the Baltic seabed were cut in quick succession, government authorities and telecom companies said.

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