Complex sentence: There is documented evidence and testimony recounting the brutality of the French guards in Drancy and the brutal conditions imposed on the people including small children who, upon their arrival, were immediately separated from their parents and deported to the death camps.
Split into simpler sentences: There is documented evidence and testimony recounting the brutality of the French guards in Drancy and the brutal conditions imposed on the inmates. Upon their arrival, small children, were immediately separated from their parents for deportation to the death camps.