WEBVTT 00:02.533 --> 00:05.266 align:left position:10%,start line:71% size:80% JUDY WOODRUFF: Almost 20 years, American embassies in Africa were attacked by al-Qaida, making 00:07.266 --> 00:10.600 align:left position:20%,start line:71% size:70% the terror group's leader, Osama bin Laden, an infamous household name, three years before 00:11.700 --> 00:15.133 align:left position:20%,start line:83% size:70% the horror of September 11, 2001. 00:15.133 --> 00:20.133 align:left position:20%,start line:71% size:70% During that period, MI6, which is the British foreign intelligence service, had an agent 00:20.733 --> 00:22.333 align:left position:30%,start line:89% size:60% inside al-Qaida. 00:22.333 --> 00:24.533 align:left position:10%,start line:89% size:80% He has now unmasked himself. 00:24.533 --> 00:27.866 align:left position:10%,start line:77% size:80% And he spoke with Jonathan Rugman of Independent Television News. 00:27.866 --> 00:31.366 align:left position:10%,start line:83% size:80% JONATHAN RUGMAN: He calls himself Aimen Dean. 00:31.366 --> 00:36.366 align:left position:10%,start line:77% size:80% For eight years, he worked for MI6 as a double agent, mostly inside al-Qaida. 00:38.300 --> 00:42.733 align:left position:10%,start line:77% size:80% And now one of the West's most important spies has broken cover to tell his story. 00:44.733 --> 00:47.066 align:left position:10%,start line:77% size:80% AIMEN DEAN, Former Undercover Agent: If you spend eight years under cover, at some point, 00:47.066 --> 00:50.666 align:left position:10%,start line:83% size:80% basically, you will start to feel the effects. 00:50.666 --> 00:55.633 align:left position:10%,start line:77% size:80% JONATHAN RUGMAN: In 1996, Aimen Dean underwent al-Qaida training in Afghanistan. 00:59.533 --> 01:04.500 align:left position:20%,start line:77% size:70% The teenager from Bahrain already fought as a jihadi in Bosnia. 01:05.866 --> 01:09.900 align:left position:10%,start line:83% size:80% Now he swore an oath of allegiance to Osama bin Laden. 01:09.900 --> 01:11.333 align:left position:20%,start line:89% size:70% Did he impress you? 01:11.333 --> 01:14.033 align:left position:10%,start line:83% size:80% You write that he was tall, he was softly spoken. 01:14.033 --> 01:19.033 align:left position:10%,start line:77% size:80% AIMEN DEAN: Absolutely, someone who was -- who could have had a luxury life in Saudi Arabia, 01:22.600 --> 01:27.600 align:left position:10%,start line:77% size:80% someone basically who could have had an easy life, and yet he gave all that up in order 01:28.533 --> 01:30.566 align:left position:30%,start line:83% size:60% to serve a cause bigger than him. 01:30.566 --> 01:35.533 align:left position:10%,start line:77% size:80% JONATHAN RUGMAN: Al-Qaida's bombings of U.S. embassies in Kenya and Tanzania left hundreds 01:36.666 --> 01:41.466 align:left position:20%,start line:83% size:70% dead and Aimen Dean outraged by the carnage. 01:45.166 --> 01:50.133 align:left position:10%,start line:71% size:80% Then three years later, September the 11th, almost 3,000 people killed, and Dean had known 01:51.400 --> 01:53.500 align:left position:20%,start line:89% size:70% one of the hijackers. 01:53.500 --> 01:58.333 align:left position:10%,start line:77% size:80% By now, though, he'd moved to London, using the need for medical treatment as cover to 01:59.100 --> 02:01.200 align:left position:20%,start line:89% size:70% become a British spy. 02:01.200 --> 02:05.700 align:left position:10%,start line:77% size:80% Your job was to carry radios and phones into Afghanistan that enclosed MI6 bugging devices. 02:08.366 --> 02:09.600 align:left position:30%,start line:89% size:60% Was that it? 02:09.600 --> 02:11.766 align:left position:20%,start line:83% size:70% AIMEN DEAN: Well, more than that. 02:11.766 --> 02:16.066 align:left position:20%,start line:71% size:70% My job was basically to report on locations of camps, the new training methods, the individuals 02:19.400 --> 02:24.400 align:left position:10%,start line:77% size:80% coming in and out, and also at the same time keeping up with al-Qaida's WMD program at 02:25.733 --> 02:27.866 align:left position:30%,start line:89% size:60% the time. 02:27.866 --> 02:30.533 align:left position:10%,start line:77% size:80% JONATHAN RUGMAN: But if you were doing all that, why did an attack like September the 02:30.533 --> 02:32.566 align:left position:30%,start line:89% size:60% 11th happen? 02:32.566 --> 02:36.033 align:left position:10%,start line:77% size:80% AIMEN DEAN: If you wanted to stop 9/11, you have to have at least 12 spies inside al-Qaida, 02:36.033 --> 02:38.866 align:left position:10%,start line:83% size:80% and each one inside one of the different departments. 02:38.866 --> 02:41.433 align:left position:20%,start line:83% size:70% Only then, you could have stopped it. 02:41.433 --> 02:44.966 align:left position:10%,start line:71% size:80% JONATHAN RUGMAN: What was your biggest intelligence coup, as far as you're concerned, in terms 02:44.966 --> 02:47.000 align:left position:10%,start line:89% size:80% of what you managed to prevent? 02:47.000 --> 02:49.733 align:left position:20%,start line:83% size:70% AIMEN DEAN: Well, there were several. 02:49.733 --> 02:54.700 align:left position:10%,start line:77% size:80% I mean, there was a plot to attack the New York subway with chemical weapons, a chemical 02:57.733 --> 03:02.700 align:left position:10%,start line:77% size:80% device that was invented during my time actually in that specialist lab in Afghanistan. 03:04.333 --> 03:08.800 align:left position:20%,start line:77% size:70% And I was reporting on it regularly to the U.K. secret services. 03:10.266 --> 03:13.433 align:left position:10%,start line:83% size:80% JONATHAN RUGMAN: He never visited MI6 headquarters. 03:13.433 --> 03:18.300 align:left position:10%,start line:77% size:80% Before any meeting, he would call his handlers from a series of phone boxes to be given a 03:18.300 --> 03:23.300 align:left position:10%,start line:77% size:80% rendezvous and to allow spotters from MI5 to check he wasn't being followed. 03:25.266 --> 03:29.833 align:left position:10%,start line:77% size:80% His spying career ending in 2006 during a boat ride on holiday in Paris. 03:31.900 --> 03:36.166 align:left position:10%,start line:77% size:80% He was told the Americans had leaked details of his identity to a journalist. 03:37.033 --> 03:39.300 align:left position:10%,start line:89% size:80% MI6 ordered him back to London. 03:39.300 --> 03:44.300 align:left position:10%,start line:77% size:80% Do you have any lasting regret that you betrayed people whom you had become friends with? 03:45.366 --> 03:47.266 align:left position:30%,start line:89% size:60% AIMEN DEAN: No. 03:47.266 --> 03:51.600 align:left position:10%,start line:89% size:80% I did not betray a state. 03:51.600 --> 03:54.733 align:left position:10%,start line:83% size:80% I betrayed a bunch of criminals, as simple that. 03:54.733 --> 03:59.700 align:left position:10%,start line:77% size:80% JONATHAN RUGMAN: Aimen Dean lives quietly somewhere in the British Isles, his code name, 04:01.800 --> 04:05.666 align:left position:10%,start line:77% size:80% Lawrence, as in Lawrence of Arabia, an identity he left behind over a decade ago. 04:07.500 --> 04:10.600 align:left position:10%,start line:77% size:80% JUDY WOODRUFF: That was Jonathan Rugman of Independent Television News.