A prominent British human rights barrister, who has fought high-profile cases in Hong Kong, has joined the legal team preparing to sue the government over its alleged role in secretly sending a Libyan dissident and his family to the torture chambers of former dictator Muammar Gaddafi. Senior counsel Paul Harris said he was confident Sami al-Saadi had a strong case, given the cache of classified papers unearthed in Tripoli, which implicate security officials in Hong Kong alongside British, American and Libyan spy agencies in the illegal extradition. "The documents I've seen show a very strong case," he said. "They clearly indicate the British and Hong Kong governments' involvement in sending Mr Saadi and his family back to Libya where it was overwhelmingly likely that he would be tortured or worse." Saadi was jailed for six years and says he was repeatedly beaten, subjected to electric shocks and threatened with death. He was only freed when Gaddafi was ousted in August last year. He reportedly weighed just 44kg and was close to death. Harris said the British government's decision this month to pay Saadi and his family £2.2 million (HK$25 million) in compensation - without admitting any liability - reflected the seriousness of the allegations. "It's a substantial sum and an indication of how strong the case is," he said. Saadi, an outspoken opponent of the late Gaddafi's regime who was regarded by the West as a terrorist with links to al-Qaeda, claims the Hong Kong government conspired with the CIA, MI6 and Libyan spies to secretly extradite his family from Chek Lap Kok airport to Tripoli via Bangkok on a privately chartered Egypt Air plane in March 2004. Saadi is also suing the government for the "inhuman and degrading" treatment he and his family endured during two weeks of unlawful detention at Chek Lap Kok. His four children were all aged between six and 12 at the time. They and their mother were imprisoned for two months on their return to Libya. A former chairman of the English Bar Council's Human Rights Committee and founder of the Hong Kong Human Rights Monitor, Harris called on the government to settle the matter through compensation. "I would hope the Hong Kong government would take a sensible option. It would save a great deal of time," he said. "If that doesn't happen, then the case will be fought vigorously." Justice officials failed to respond to a pre-action letter sent by Saadi's lawyers in June. A spokeswoman for the Department of Justice said it could not comment on individual cases. Harris said Saadi's case was the first known case of rendition involving the Hong Kong government. As a signatory to the 1984 UN Convention Against Torture, the city is obligated not to send people back to a state where they could be tortured. Harris represented Christina Chan Hau-man, who was arrested for waving a Tibetan flag during Hong Kong's Olympic torch relay in June 2008. He was earlier involved in rights cases involving non-permanent residents and domestic helpers.