Robert Hanssen, a former FBI agent who infamously spied for Russia for two decades, was found dead in his Colorado supermax prison cell, according to the Bureau of Prisons.
Hanssen, 79, was arrested in 2001 and sentenced to life in prison after pleading guilty to selling highly classified material to first the Soviet Union and then Russia in return for more than $1.4m in diamonds, cash and foreign bank deposits.
