"Mustafa Muhammad Ahmad", is the presumed alias of a terrorist operative who is believed to have provided funds to Mohammed Atta, the suspected hijack ringleader in the September 11, 2001 attacks. Although the identity of this person is not entirely certain, it has been suggested, by CNN and others, that Mustafa Ahmed is in fact the British-born Ahmed Omar Saeed Sheikh, who in 2002 was found guilty of the murder of the American investgative journalist, Daniel Pearl.
'Mustafa Muhammad Ahmad' was named as an alias of a "Shaykh Sai'id" in a list of terrorists and terrorist organisations annexed to Executive Order 13224, issued in the aftermath of the attacks.