Abdel-Rahman has strong ties to al Qaeda and is seen as a key theological force behind the terror group. He is an influential figure for Egyptian Islamic Jihad, most of whose members joined al Qaeda. He has been mentioned often by Osama bin Laden and his deputy, Ayman al-Zawahiri.

The cleric has been imprisoned since 1995 for inspiring the 1993 World Trade Center attack and a thwarted plot to attack bridges and tunnels, an FBI building and U.N. headquarters in New York.

The FBI bulletin includes what it said was Abdel-Rahman's last will and testament distributed at an al Qaeda news conference in 1998: "My brothers, if they kill me -- which they will certainly do -- hold my funeral and send my corpse to my family but do not let my blood be shed in vain. Rather extract the most violent revenge."

The bulletin is intended to alert all those in law enforcement of the possibility of a threat.