An undercover MI5 operation uncovered that a spy working at Berlin’s British Embassy was selling secrets to Russia, and he was sentenced to 13 years and two month imprisonment.
David Smith, age 58, attempted to harm Britain’s interests through passing details of the Embassy and its staff to cash payments. A judge found that the spy had pleaded guilty.
Tom Symonds, BBC Home Affairs correspondent, explains what Mr Smith did and how he was stopped.
Video by Mattea Bulo & James McFadden
