Another tip. Two sources. The first is a blog article on the 'Forest Brothers' resistance in Estonia:https://globalecco.org/226

Interesting to note Estonia is only 45,227 sq kms (or 17k sq miles), there were only 130 hiding in the forests - active over a small area - and in March 1949 30k suspected contacts were deported.

There is an article too on the 'Forest Brothers' after the 1940 "voluntary union" with the USSR. Note then there were 12k 'Brothers'. Link:https://globalecco.org/estonias-fore...s-and-outcomes

There is British aspect to the Cold War period, covered in a 1993 book, with SIS mounting operations and being totally outfoxed by the KGB:
http://www.amazon.com/Red-Web-MI6-Ma.../dp/0749314788