An anonymous reader quotes The Hill: Russian submarine activity around undersea cables that provide internet and other communications connections to North America and Europe has raised concerns among NATO officials, according to The Washington Post. NATO officials say an unprecedented amount of Russian deep-sea activity, especially around undersea internet lines, constitutes a newfound "vulnerability" for NATO nations. "We are now seeing Russian underwater activity in the vicinity of undersea cables that I don't believe we have ever seen," said NATO submarine forces commander and U.S. Navy Rear Adm. Andrew Lennon. "Russia is clearly taking an interest in NATO and NATO nations' undersea infrastructure."
"The Russian Defense Ministry did not respond to a request for comment about the cables," reports the Washington Post, adding that "prowling around" the cables "could give the Kremlin the power to sever or tap into vital data lines, officials said."

They cite the commander of NATO's submarine forces, who says "We know that these auxiliary submarines are designed to work on the ocean floor, and they're transported by the mother ship, and we believe they may be equipped to manipulate objects on the ocean floor."