The Finnish Coast Guard says that jamming of satellite positioning in the Gulf of Finland has caused vessels to stray from their routes. The jamming has continued at an increasing rate since April, and the Coast Guard has had to warn vessels not to run aground.
The Coast Guard said the disturbances have led to malfunctions in vessels' Automatic Identification Systems (AIS), which enable electronic navigation.
"In recent weeks, we have also observed that (AIS) devices have been intentionally turned off, and thus the location information has been spoofed in online location systems...so that an incorrect location is shown for the vessel," commander Pekka Niittyla of the Gulf of Finland Coast Guard told news agency Reuters.
Niittyla said these so-called "shadow fleets" of ships spoofing their locations was a new phenomenon that the Coast Guard has detected around ten times so far by different tankers visiting Russian ports around St. Petersburg.
"Based on our assessment, this is related to the evasion of sanctions or their consequences," he said. "For example, if a country buying Russian oil does not want to reveal that the oil was purchased from Russia, the seller or vessel might use spoofing to make it seem like the vessel had not visited Russia."
The Coast Guard said it believes Russia is jamming the signals to protect its oil ports located in the eastern end of the Gulf of Finland from Ukrainian air strikes or drones.
Last week, Finland's Interior Minister Lulu Ranne (Finns) accused Russia of interfering with navigation systems. Russia has denied any involvement.
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