"Reports of satellite navigation problems in the Black Sea suggest that Russia may be testing a new system for spoofing GPS, New Scientist has learned. This could be the first hint of a new form of electronic warfare available to everyone from rogue nation states to petty criminals.".
https://www.newscientist.com/article/2143499-ships-fooled-in-gps-spoofing-attack-suggest-russian-cyberweapon/
"After reports of an apparent mass and blatant GPS spoofing attack involving more than 20 vessels in the Black Sea last month, navigation experts and maritime executives are scratching their heads and the president of the Resilient Navigation and Timing (RNT) Foundation is hoping this latest incident will help spur more action toward building an eLoran complement and backup for GPS."
http://www.insidegnss.com/node/5555
Calibrate your sextant.
Things in Russia becomes really crazy these days. Also, GPS spoofing was reported in Moscow near Kremlin.