A top U.S. defense official said it was "no coincidence" that recent Islamic State videotapes of the savage executions of Jordanian and Japanese hostages showed the victims wearing orange jumpsuits, "believed by many to be the symbol of the U.S. detention facility at Guantanamo Bay."

Brian McKeon, principal undersecretary of defense for policy, made that point in prepared testimony for a Senate Armed Services Committee hearing on Thursday on the controversial facility.

He said President Barack Obama and his national security team all believe that the continued operation of the Guantanamo Bay detention center "is used by violent extremists to incite local populations," McKeon said.