Bulgarian submarines according to a C.I.A. report dated 13 November 1952

An item reported that the submarine flotilla with her headqarters at Ochakov, Soviet Union (=Ukraine). In 1947 were three submarine with a displacement of more as 500 ton handed over by the Soviet Union to Bulgaria. However, the submarines were stationed in the Soviet harbors Odessa, Ukraine and Ochakov, Ukraine.

Source

C.I.A. report no. CIA-RDP83-00415RO12700120006-1