Ethnic persecution (6)
I believe the answer is:
pogrom
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">ethnic persecution</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that pogrom is a type of ethnic riot)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for pogrom that I've seen before include "An organised massacre of a people" , "Racial massacre" , "Organised massacre of Jews" , "Mass slaughter" , "Organised persecution of an ethnic group" .)