Operation Reinhard Mass Cremation: Bone .
In some camps, such as Janowska, outside Lvov, Poland, a bone crushing machine may have been used. The ashes were then reburied in the empty graves. There is documentary evidence about how the ashes were handled in Treblinka. Kurt Franz was the last commandant of Treblinka. Although photographs were explicitly forbidden by SS directive, Franz took numerous pictures of the camp. He .