Operation Poro (the Finnish for Reindeer), was a planned invasion of the north Scandinavian peninsula by the Soviets. The plan originated in 1932 and was rehashed during the period 1935 to 1936. The plan was for a Soviet offensive through northern Finland and Sweden with the aim of occupying northern Norway. The Norwegian Labour Party was involved in similar efforts already from the early 1920s to the early 1930s, as exposed in a parliamentary report in 1932.
The original article can be found at Operation Poro and the edit history here.