Aimen Dean, known in al-Qaeda circles simply as ‘Ramzi’, became radicalized in the first half of the 1990s in response to the Bosnian War. At that time, he traveled from his home country of Saudi Arabia to Bosnia, where he joined large numbers of foreign Muslim fighters who fought in support of Bosnian-Muslim forces. In subsequent interviews, Dean has said that he continues to view his participation in the Bosnian War as an “ethical and moral” act in defense of a “defenseless population”. Following the end of the Bosnian War, Dean joined many foreign-born fighters who followed al-Qaeda co-founder Osama bin Laden to Afghanistan. While there, he pledged allegiance to bin Laden and gained his trust.

Dean’s task in Afghanistan was to train new al-Qaeda recruits in Islamic theology and history. But he was also tasked with combat duties, which included bomb-making. He witnessed the drastic shift in al-Qaeda’s raison d’être from a group ostensibly fighting to defend Muslims under attack, to a center of a violent campaign against the West. Dean has stated that during his first period in Afghanistan, he sincerely believed that the West was involved in a systematic campaign to destroy Islam and Muslims. Gradually, however, Dean’s views began to conflict with those of al-Qaeda’s leaders. He especially objected to the use of suicide bombers and the deliberate targeting of civilians by al-Qaeda fighters. His disillusionment with al-Qaeda peaked in August of 1998, when the organization targeted the United States embassies in Kenya and Tanzania in coordinated strikes.

During a leave of absence from al-Qaeda’s Afghanistan stronghold, Dean was approached by the United Kingdom’s Secret Intelligence Service, more commonly known as MI6. He says that he quickly agreed to work as a spy for the British agency and did so from 1998 until 2007, when he claims that his cover was blown. Dean has now written a book, co-authored with two CNN reporters, Paul Cruickshank and Tim Lister. Entitled Nine Lives: My Time As MI6’s Top Spy Inside al-Qaeda, the book is due to appear in stores on June 7.