No charges will be brought over allegations of the rendition of two families to Libya 12 years ago.
There is "insufficient evidence" to press criminal charges as part of the investigation into how the Belhadj and Al Saadi families were handled, the Crown Prosecution Service said.
The CPS, working with the Metropolitan Police on the investigation known as Operation Lydd which was set up to consider complaints of ill treatment against detainees, looked at "a large number" or records, people and organisations including the security services and Government departments.
Abdel Hakim Belhaj and Sami al-Saadi, along with members of their families, were kidnapped and sent to face punishment in Libya in 2004.
Mr Belhadj and his wife, Fatima Boudchar accused former Foreign Secretary Jack Straw and an ex-senior MI6 officer, Sir Mark Allen, of being responsible for their forced return to Colonel Gaddafi's Libya in March 2004 where they suffered ill-treatment.
Sue Hemming, head of the CPS's Special Crime and Counter Terrorism Division, said: "Following a thorough investigation, the CPS has decided that there is insufficient evidence to charge the suspect with any criminal offence.
"We made our decision based upon all the available admissible evidence and after weighing up all of the information we have been provided with."
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