A secret Russian electronic warfare system is disrupting the GPS guidance of airliners and ships on NATO's eastern flank. The interference spans from Finland through the Baltic states to Poland, according to General Martin Harem, commander of the Estonian Defence Forces. “What we have seen is a malfunctioning of GPS for ships and air traffic,” General Martin Harem told Telegraph UK. He added that NATO doesn’t know “if they [Russia] want to achieve something or just practise and test their equipment”. Estonia is the first NATO member to directly accuse Russia of the disruption. A British thinktank expert said the Russian electronic warfare system, Tobol, was disrupting GPS signals in multiple directions. What is "Tobol" and why is Russia using it in Eastern Europe? Watch this video to know more.