State Political Directorate
The State Political Directorate (Russian: Государственное политическое управление, romanized: Gosudarstvennoe politicheskoe upravlenie), abbreviated as GPU (ГПУ), was the secret police of the Russian Socialist Federative Soviet Republic (RSFSR) from February 1922 to November 1923. It was the immediate successor of the Cheka, and was replaced by the Joint State Political Directorate (OGPU).
Source: Wikipedia — State Political Directorate (CC BY-SA 4.0)