Law firm Public Interest Lawyers (PIL) have said they had compiled thousands of allegations of abuse amounting to "war crimes of torture" or to "cruel, inhuman or degrading treatment".
They were said to include beatings, burning, electric shocks and mock executions as well as sexual assault and humiliation, including forced nakedness and forced or simulated sexual acts, with "clear patterns" emerging of the same techniques being used again and again.
In a statement PIL said:
There are considerable reasons to allege that those who bear the greatest responsibility for the crimes are situated at the highest levels, including all the way up the chain of command of the UK Army, and implicating former secretaries of state for defence and ministers for the armed forces personnel.
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