Almost immediately after the ZSU-57-2 went into production, the Council of Ministers of the Soviet Union signed decree Nr. 426-211 on April 17, 1957. The decree ordered that work be started on new types of rapid-firing self-propelled anti-aircraft guns, which were to be named "Shilka" and "Yenisei". Both types would incorporate fire control systems slaved to an on-board radar. The Yenisei was the Soviet Union's response to the M42 Duster which had been put into service in the US.
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