Antiaircraft defence of winter harbour of Budapest, Hungary increased according to a CIA report dated 16 June 1953

An item reported that in the winter of 1952-1953 the antiaircraft defence of the Budapest winter harbour was taken care of. Tugs and towed craft were fitted out with steel swivels with a diameter of circa 2 metres for mounting shore-range machineguns which yet was not done. In barracks in Budapest were men trained in handling light antiaircraft guns. Czechoslovakian, Romanian and Bulgarian shipping concerns took similar action.

Source
The report was published on www.archive.org, document number CIA-RDP80-00810A001500250007-1