Sergey Mikhaylovich Stepnyak-Kravchinsky

Sergey Mikhaylovich Stepnyak-Kravchinsky (Russian: Серге́й Миха́йлович Степня́к-Кравчи́нский; July 1, 1851 – 23 December 1895), known in the 19th century London revolutionary circles as Sergius Stepniak, was a Russian revolutionary mainly known for assassinating General Nikolai Mezentsov, the chief of Russia's Gendarme corps and the head of the country's secret police, with a dagger in the streets of St Petersburg in 1878.