Details have emerged from the KGB files smuggled out of Russia in 1992 by senior KGB official Vasili Mitrokhin, which Britain declassified last week. Some of the files relate to an operation code-named Progress in which 15 Russian agents were sent to Czechoslovakia in the spring of 1968 to undermine the Prague Spring pro-democracy movement. They targeted journalists from Czechoslovak radio and television, academics from Charles University, members of the Christian Democratic Party and writers such as Pavel Kohout and Milan Kundera. Operation Progress was launched by then KGB chief Jurii Andropov. The files can be viewed at Cambridge University.