A spy at the heart of Nato may have passed secrets on the US missile shield and cyber-defence to Russian Intelligence, it has emerged. Herman Simm, 61, an Estonian defence ministry official who was arrested in September, was responsible for handling all of his country's classified information at Nato, giving him access to every top-secret graded document from other alliance countries. He was recruited by the Russians in the late 1980s and has been charged in Estonia with supplying information to a foreign power. Several investigation teams from both the EU and Nato, under the supervision of a US officer,...