That Dr. Ayman al-Zawahiri, bin Laden’s right-hand man and the leader of the global jihad movement since bin Laden’s death in May 2011, spent almost a half-year in the mid-1990s in the custody of Russian intelligence is admitted by both sides and is a matter of public record.
Just as significant, Zawahiri’s Russian sojourn occurred at a pivotal point in the development of al-Qa’ida; the shift in strategy, resulting in attacks on the “far enemy” (i.e. the United States), the road leading to 9/11, occurred after Zawahiri’s imprisonment by the Russians.
While the idea that Russian intelligence may have developed a relationship with Zawahiri sounds fantastic to most in the West, the notion is far from implausible, and is consistent with known Soviet/Russian espionage practices. During the Cold War, the KGB had robust ties with many terrorist groups, including several from the Middle East.
https://www.businessinsider.com/exploring-al-qaedas-murky-connection-to-russian-intelligence-2014-6
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