S. Stepniak

Sergei Mikhailovich Stepniak-Kravchinskii (Russian: Сергей Михайлович Степняк-Кравчинский, Ukrainian: Сергій Степняк-Кравчинський; 13 July 1851 – 23 December 1895), known in 19th-century London revolutionary circles as Sergius Stepniak, was a Russian revolutionary of Ukrainian descent. He is mainly known for assassinating General Nikolai Mezentsov, chief of Russia's Gendarme corps and head of secret police, with a dagger in the streets of St. Petersburg in 1878.