Stalin appointed Andrei Zhdanov to succeed Kirov as the governor of Leningrad. Zhdanov was a young, capable, and ruthless man, who had purged the Komsomol of deviationists and distinguished himself in arrogant attacks on Tomsky during the fight in the trade unions. Stalin could rely upon him to destroy the hornets' nest in Leningrad. In the spring of 1935 tens of thousands of suspect Bolsheviks and their families were deported from Leningrad to northern Siberia.

In Tsarist days political offenders had enjoyed certain privileges and been allowed to engage in self-education and even in political propaganda. Oppositional memoranda, pamphlets, and periodicals had circulated half freely between prisons and had occasionally been smuggled abroad. Himself an ex-prisoner, Stalin knew well that jails and places of exile were the 'universities' of of the revolutionaries. Recent events taught him to take no risks. From now on all political discussion and activity in the prisons and places of exile was to be mercilessly suppressed; and the men of the opposition were by privation and hard labour to be reduced to such a miserable, animal-like existence that they should be incapable of the normal processes of thinking and of formulating their views.