Reuters:

WASHINGTON - Osama bin Laden's al Qaeda network, whose operatives have used fraudulently obtained passports for international travel, has acquired stolen blank Saudi passports, the FBI said on Wednesday. In its weekly intelligence bulletin to local law enforcement officials, the FBI said the unissued Saudi passports are authentic and have key security features that allow them to pass routine examination.

"Numerous al Qaeda terrorists have also carried Saudi passports issued in the Holy Capital, another term for the city of Mecca," the FBI said.

It said past FBI intelligence bulletins have noted the use by Islamic extremists of fraudulent Pakistani passports and al Qaeda's use of altered or fraudulent Colombian identification cards and passports.

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See also, the FBI's Congressional report on "The State of the Terrorist Threat Facing the United States."