Saefkow/sevekow

Hello,
I am Joerg-R. Kropp from Berlin, I am new to this list and hope to have
a lot of interesting discussions.
My focus is currently on the SAEFKOW family (with various spellings).
They lived in Mecklenburg-Strelitz at several places. Many of them were
fisherman (Pachtfischer) who lived for generations at some of the many
lakes.
A famous member of that family was Anton Saefkow, a communist
underground fighter who was killed by the Nazis in the WW2.

I am interested in any informaton or connection to that family.