GRU Russia: The spy agency and global cyber-attacks explained

Emily Ferris, from the Royal United Services Institute defence think tank, said: "GRU is one of three of Russia's intelligence agencies whose activities often overlap, the others are the Federal Security Services (FSB) and the Foreign Intelligence Services (SVR). The FSB has a broader remit, including counter-terrorism, border control and domestic surveillance, but all the agencies are in competition for resources and funding."