The FBI apparently conducted a lengthy investigation of Berg in captivity because they were checking out a possible friendship or other tie with an Arab at the University of Oklahoma who was under scrutiny in connection with the Sept. 11, 2001, terror attacks.
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"He'd made some contact with Arab kids at the University of Oklahoma - that's what the FBI was checking into...a guy from Oklahoma," the source said. He said the FBI wanted to know if the Oklahoma connection was "why he came over here."...He said the Oklahoma contact was "related to somebody who was involved in 9/11." But he didn't know if that person was jailed al Qaeda supporter Zacarias Moussaoui, who attended the University of Oklahoma close to when Berg was there in 2000