Hassan Mustafa Osama Nasr, also known as Abu Omar, is an Egyptian cleric. In 2003, he was living in Milan, Italy, from where he was kidnapped and tortured in Egypt. This "Imam rapito affair" prompted a series of investigations in Italy, culminating in the criminal convictions of 22 CIA operatives, a U.S. Air Force colonel, and two Italian accomplices, as well as Nasr, himself.

The Abu Omar Case was the abduction and transfer to Egypt of the Imam of Milan Hassan Mustafa Osama Nasr, also known as Abu Omar. The case was picked by the international media as one of the better-documented cases of extraordinary rendition carried out in a joint operation by the United States' Central Intelligence Agency (CIA) and the Italian Military Intelligence and Security Service (SISMI) in the context of the global war on terrorism declared by the George W. Bush administration.