
1) KGB ancestor
Found on
https://www.crosswordclues.com/clue/cheka

Soviet secret police formed in late 1917 to identify, investigate and deal with potential enemies of the state. CHEKA agents operated outside any legal framework and used a wide variety of methods, many intimidatory or brutal, to extract information and/or deal with dissidents.
Found on
http://alphahistory.com/russianrevolution/russian-revolution-glossary-a-l/

Cheka (ЧК – чрезвыча́йная коми́ссия chrezvychaynaya komissiya, Emergency Commission, tɕɪˈka) was the first of a succession of Soviet state security organizations. It was created on December 20, 1917, after a decree issued by Vladimir Lenin, and was subsequently led by Felix Dzerzhinsky, a Polish aristocrat turned commu...
Found on
http://en.wikipedia.org/wiki/Cheka

The political police created by the Bolsheviks in 1917; supposed to be dissolved when the new regime, under Lenin, had defeated its enemies and secured its power. But the Vecheka, also known as the Cheka, continued until 1922, becoming the leading instrument of terror and oppression as well as the predecessor of other secret police organizations. M...
Found on
http://soviethistory.msu.edu/glossary/

early Soviet secret police agency and a forerunner of the KGB (q.v.).[5 related articles]
Found on
http://www.britannica.com/eb/a-z/c/62

Secret police operating in the USSR between 1917 and 1923. It originated from the tsarist Okhrana (the security police under the tsar from 1881 to 1917), and became successively the OGPU (GPU)...
Found on
http://www.encyclo.co.uk/local/20688

The Cheka was the first Soviet security and intelligence agency. It was formed on the 20th of December 1917, six weeks after the Bolshevik Revolution.
Found on
http://www.probertencyclopaedia.com/browse/FC.HTM

The Cheka was a Russian patrol vessel of 500 tons displacement launched in 1935. The Cheka was powered by diesel engines providing a top speed of 16 knots, and was armed with one 4 inch gun; four 37 mm anti-aircraft guns and was fitted for mine laying and mine sweeping.
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http://www.probertencyclopaedia.com/browse/RC.HTM

the Bolshevik secret police, forerunner of the KGB.
Found on
http://www.uleth.ca/lib/digitized_collections/ourheritage/Great_Adventures/

(in the Soviet Union) the state secret-police organization (1917–22), succeeded by the GPU. Cf.
Found on
https://www.infoplease.com/dictionary/cheka
(Vserossiyskaya chrezvychaynaya komissiya po bor'be s kontrrevolyutsiyey i sabotazhem--VChK) All-Russian Extraordinary Commission for Combating Counterrevolution and Sabotage. The political police created by the Bolsheviks in 1917, the Cheka (also known as the Vecheka) was supposed to be dissolved when the new regime, under Vladi...
Found on
https://www.photius.com/countries/estonia/glossary/index.html
No exact match found.