The Soviet motor tug Estonia active on the Danube according to a CIA report dated 10 June 1955

An item dealing with the Danube shipping movements reported that on 19 February 1955 was sighted on the position DKM 1754 the Soviet tug ms Estonia executing trials for her completion at Komarno. Was to be used for service on the river Djenpr.

Source
The report was published on www.archive.org, document number CIA-RDP80-00810A007000090002-6