In the movie series XIII the main character was imprisoned in something they called "a rendition camp in Romania". In the movie it looked just like a prison. He was put there on the order of NSA or CIA or some agency without a proper sentence, they kind of "deposited" him there because they had considered him dangerous.
What is the exact meaning of the word rendition in the phrase rendition camp? I cannot find the definition of the phrase and none of the definitions of the rendition itself does not make sense (a performance or interpretation, a translation of a piece of writing, visual representation or reproduction).