A shock video of Egyptian police aiming rubber bullets directly at protesters' eyes has galvanised opinion against security forces' brutal methods to quell new mass protests that have left dozens dead.
The video, viewed thousands of times on YouTube before a private television broadcast it, has shocked the country.
It shows police officers cheering each other as they aimed for the eyes of protesters during clashes in Mohammed Mahmud street, which leads to the interior ministry.
"In his eye! It was in his eye! Bravo, my friend!" an officer told his colleague in the footage, which showed the shooter's face.
Activists have been distributing leaflets with a picture of the man, whose name is still unknown, promising a reward of 5,000 Egyptian pounds ($833) for anyone who provides information about him.
Demonstrators have gathered daily since Friday in Tahrir Square -- the symbolic heart of the protests that toppled veteran president Hosni Mubarak in February -- to demand the ruling military cede power to a civilian authority.
Demonstrators in the square have been carrying pictures of Ahmad Harrara, a 31-year-old dentist who lost one eye during the protests against Mubarak and now been injured in the other eye by a rubber bullet during the latest rallies.
Harrara has become the latest face of many campaigns to "unmask security thugs" and a new symbol of the struggle for freedom in Egypt.
Cairo's International Eye Hospital, where Harrara has been receiving treatment, has offered to treat victims of other similar shootings.
On Qasr al-Nil Bridge, which spans the Nile hard by Tahrir Square, demonstrators have covered the eyes of two large stone statues of lions that flank it in another symbolic protest against the injuries.
According to official figures, more than 2,000 people have been injured in nationwide protests since Saturday.
The interior ministry has insisted that "police did not use firearms, shotguns or rubber bullets," but instead fired "tear gas to disperse the rioters."
However, a number of journalists have been hit by rubber bullets, including an AFP correspondent struck four times over two days and an AFP photographer.
And even state television has aired interviews with people injured by rubber bullets.
For his part, presidential hopeful Mohamed ElBaradei, former head of the International Atomic Energy Agency, has denounced what he called a "massacre" and the use of "live ammunition" against demonstrators.
Three more people died in Cairo on Wednesday, a medic said, as violence which has killed dozens raged into a fifth day despite promises by Egypt's military ruler, Field Marshal Hussein Tantawi, to speed up the transition to democracy.
Riot police erected barricades on Mohammed Mahmud street, shooting tear gas and birdshot, which ricocheted off concrete buildings, sending dust and chips of cement into the tear gas-filled air, an AFP correspondent reported.
The health ministry said in a statement carried by the state MENA news agency that a total of 32 people had died since the clashes began on Saturday.