The Kirov Assassination
It is unknown whether Nikolaev had had prior dealings with the Leningrad branch of the Soviet Russian government, headed by Sergei Kirov. What is known is that Kirov had brooked the displeasure of Joseph Stalin, the head of the Soviet Communist Party, by refusing to persecute adherents of a growing Opposition movement to Stalin's leadership. At a Party congress in January 1934, Kirov demonstrated his popularity over that of Stalin, where he received the fewest negative votes of any delegate (three, as opposed to 292 for Joseph Stalin).
As Nikolaev's troubles grew, he became steadily more obsessed with the idea of "striking a blow." On October 15, 1934, he was arrested by the NKVD, allegedly for loitering around the Smolny Institute, where Sergei Kirov, the popular administrator of the Leningrad district, had his offices. In reality, the Smolny guards had discovered a loaded 7.62 mm Nagant M1895 revolver in Nikolaev's briefcase. Though Nikolaev had clearly broken Soviet laws regarding the carrying of firearms into secure government offices, the security police inexplicably released him from custody within a few hours; he was even permitted to retain his loaded revolver. Some Soviet sources later argued that Nikolaev did have a permit to carry a loaded handgun, even though handgun permits for non-Party members without cause for such a weapon in their duties were unknown in the Soviet Union, especially a man with a history of instability and grudges against the Party. Even if granted a permit, he would never have been authorized to carry such a weapon into secured Party buildings, and would have faced charges in a People's Court for doing so.
After Nikolaev's visit, the NKVD failed to augment Kirov's security; instead, it withdrew all police protection for Kirov with the exception of a police escort to Smolny and a manned security post at the entrance to his offices.
On the afternoon of December 1, 1934, Nikolaev paid a final visit to the Smolny Institute offices. With Stalin's alleged approval, the NKVD had previously withdrawn the remaining guards manning the security desk at Smolny. Unopposed, Nikolaev made his way to the third floor, where he shot Kirov in the back of the neck with his Nagant revolver. As former Soviet official and author Alexander Barmine noted, "the negligence of the NKVD in protecting such a high party official was without precedent in the Soviet Union".
According to later press accounts and party communiques, which were never substantiated, Nikolaev was subsequently apprehended with the aid of an electrician, Platanov, who was working in the area; a friend of Kirov's, a middle-aged man named Borisev, also rushed out and helped subdue Nikolaev. Nikolaev was said to have undergone a complete collapse, and had to be carried away.
Read more about this topic: Leonid Nikolaev