Book excerpt: In 2007 Luke Harding arrived in Moscow to take up a new job as a correspondent for the British newspaper the Guardian. Within months, mysterious agents from Russia's Federal Security Service - the successor to the KGB - had broken into his flat. He found himself tailed by men in cheap leather jackets, bugged, and even summoned to Lefortovo, the KGB's notorious prison. The break-in was the beginning of an extraordinary psychological war against the journalist and his family. Vladimir Putin's spies used tactics developed by the KGB and perfected in the 1970s by the Stasi, East Germany's sinister secret police. This clandestine campaign burst into the open in 2011 when the Kremlin expelled Harding from Moscow - the first western reporter to be deported from Russia since the days of the Cold War. Mafia State: How one reporter became an enemy of the brutal new Russia is a brilliant and haunting account of the insidious methods used by a resurgent Kremlin against its so-called "enemies" - human rights workers, western diplomats, journalists and opposition activists. It includes unpublished material from confidential US diplomatic cables, released last year by WikiLeaks, which describe Russia as a "virtual mafia state". Harding gives a unique, personal and compelling portrait of today's Russia, two decades after the end of communism, that reads like a spy thriller.