Soviet prison camp (5)
I believe the answer is:
gulag
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">soviet prison camp</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for gulag that I've seen before include "Former prison camp in the USSR" , "Labour camp for political prisoners" , "Labour administration" , "Soviet prison camps" , "Soviet detention camp" .)