Cherif Kouachi, one of the brothers responsible for the Charlie Hebdo attacks, spent 20 months in Fleury-Merogis prison just outside Paris, where he crossed paths with a radical imam with ties to Osama bin Laden.This photo shows the men's building in May 2014. Charles Platiau/Reuters/Landov hide caption

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Police officers look for an escaped suspect Jan. 9 in Porte de Vincennes in Paris, France. Hayat Boumeddiene, 26, escaped and is wanted in connection with the murder of a policewoman. Aurelien Meunier/Getty Images hide caption

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Ana and John Conley, parents of defendant Shannon Conley, exit the U.S. Federal Courthouse in Denver following their daughter's plea hearing on Sept. 10. Shannon Conley, 19, pleaded guilty on a charge that she intended to wage jihad. Brennan Linsley/AP hide caption

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