In the latest book of Prof. Jan Grabowski about the Polish police during World War II, there is also information about Sokołów, Węgrów and Siedlce. The author quotes many archival records and the book by Simcha Poliakewicz translated by us.
Grabowski's book will be published in Polish in March and in English probably next year. We encourage you to read it!
https://czarne.com.pl/katalog/ksiazki/na-posterunku