Protesters reacted angrily to Egyptian media reports of a film produced in the US that mocks the prophet Muhammad.
Hundreds of protesters gathered in front of the embassy, alternating religious slogans with chants against the US or President Obama. Some climbed over the wall and tore down the American flag, raising instead a black flag with an Islamic inscription that is often associated with Islamic extremists.
Some in the crowd were ultraconservative Islamists known as Salafis. Others were simply Muslims who were upset that their prophet had apparently been maligned in the US. Several Christians joined the crowd to protest the reported insults to Muhammad.
"These insults are not just against the prophet Muhammad, peace be upon him, but against the whole Muslim community," says teacher Abdullah Ibrahim Mohamed, who explains he heard about the film from media and Facebook. He has not seen the film but heard that it "showed the prophet as a very bad man."
"We want to send Americans a message that they should respect our religion, and respect our prophet. We do no harm to them," he says.
Angry demonstrators have periodically targeted US installations abroad over perceived insults to Islam, particularly following the deepened US involvement in the Muslim world after Sept. 11, 2001. Such protests have proven challenging to American officials, who must balance US rights to free speech with a desire for greater cooperation in the region.
Trying to strike that balance, the embassy in Cairo issued a statement earlier today in expectation of the protest condemning "continuing efforts by misguided individuals to hurt the religious feelings of Muslims as we condemn efforts to offend believers of all religions."