Abdulhakim Belhaj is now a top Libyan military leader. Belhaj was kidnapped in Bangkok Thailand apparently through a CIA operation with help from the UK. He was then rendered to Libya to be incarcerated by Gadaffi and tortured. A letter found in the UK ambassador's residence by rebels congratulated Gadaffi when he took control of Belhaj or his air cargo as the group called him.
Before this revelation the UK denied any role in the rendition. The M16 UK spy group was also involved in the rendition of another Islamist Sami Saadi who is still recovering from injuries suffered while in a Gadaffi prison.
M16 officials were concerned that Belhaj was helping Al-Qaeda to recruit among regional groups in Libya. Belhaj has launched a suit in the UK for his rendition and torture. The suit will probably never go to court because of national security reasons but perhaps rather than face adverse publicity he might receive compensation from the government out of court. For more see this article.