In the fall of 1934, the Forbidden Border Zone along the western border of the Soviet Union was established, where nobody could appear without special permission issued by the NKVD. It was officially only 7.5 km deep initially, but along the Estonian border it extended to as much as 90 km. The zone was to be cleansed of Finnic and other peoples who were considered "politically unreliable" by the regime. Starting from the 1929, the Soviet authorities carried out mass deportations of the Ingrian Finnish population of the oblast, which constituted the majority in many rural localities as late as in the beginning of the century, to the east, replacing them with people from other parts of the Soviet Union.