What was the revolutionary group that assassinated nicholas II?

Nicholas II, the last Emperor of Russia, was not directly assassinated by a specific revolutionary group; instead, he and his family were executed by Bolsheviks in July 1918. The Bolsheviks, a faction of the Marxist Russian Social Democratic Labour Party led by Vladimir Lenin, sought to eliminate the imperial family to prevent any potential restoration of the monarchy during the Russian Civil War. This act was part of a broader effort to consolidate power and eliminate opposition following the October Revolution of 1917.