The U.S. seized a son-in-law of Osama bin Laden who once served as an al Qaeda spokesman and flew him to New York to face trial, an antiterrorism coup that casts light on the group's murky relationship with Iran.

Sulaiman Abu Ghaith, who was captured in Jordan, has been talking to Federal Bureau of Investigation agents for several days in New York City, according to multiple people familiar with the case. He was captured after leaving Iran, which has sheltered remnants of the global terror group.

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