CAIRO // Her screams were not drowned out by the clamour of the crazed mob of about 200 men in Tahrir Square. Hands reached towards the woman in the red shirt in an assault that lasted less than 15 minutes but felt more like an hour.
She was pushed by the sea of men for about a block into a side street. Many of the men were trying to break up the frenzy, but it was impossible to tell who was helping and who was assaulting. Pushed against the wall, the unknown woman's head finally disappeared. Her screams grew fainter, then stopped. Her slender frame had given way. She apparently had passed out.
Reports of assaults on women in Tahrir Square, the centre of the uprising that forced Hosni Mubarak to step down last year, have been on the rise with a new round of mass protests to denounce a mixed verdict against the former leader and his sons in a trial last week.
The attack on Tuesday was the last straw for many and activists met the next day to organise a campaign to prevent sexual harassment.
"Enough is enough," said Abdel-Fatah Mahmoud, a 22-year-old engineering student, who met with friends on Wednesday to organise patrols of the square. "It is unacceptable. It shouldn't be happening on our streets let alone Tahrir."
Mr Mahmoud said two of his female friends were cornered on Monday and pushed into a small passageway by a group of men in the same area where the woman in the red shirt was assaulted. One was groped while the other was assaulted, Mr Mahmoud said, refusing to divulge specifics other than to insist she was not raped.
Mona Seif, an activist, said on Wednesday she was told about three incidents in the past five days, including two that were violent.
Women played an influential role in last year's 18-day uprising but remain targets of groping and assault. They were targeted during the protests as they have been since Mubarak left office.
In a defining image of state violence against women in the post-Mubarak era, troops were captured on video stomping on the bare chest of a woman, with her blue bra showing, as other troops pulled her by the arms across the ground.
A 2008 report by the Egyptian Centre for Women's Rights says two-thirds of women in Egypt experienced sexual harassment on a daily basis.
"If you know you can get away with sexual harassment and assault, then there is an overall impunity," said the Human Rights Watch researcher Heba Morayef.
The case is more paradoxical in Tahrir, which has come to symbolise the revolution, but has lost its original lustre among Egyptians weary of more than a year of turmoil.
Women say they briefly experienced a "new Egypt", at least among the protesters who turned the square into a protected zone, but that image was marred when Lara Logan, a US correspondent for CBS television, was sexually assaulted in Tahrir on the day Mubarak stepped down.
The post-Mubarak political reality for women also has deteriorated. The 508-member parliament has only eight female legislators and women's rights groups also fear the growing power of Islamist groups will lead to new restrictions.
Activists have no idea what finally happened to the woman in the red shirt, but they have been alarmed by the rise in violent attacks on women.
"I think it is getting worse because people don't want to acknowledge it is happening or do something to reduce it," said Seif. "It is our job to put an end to it, at least in Tahrir," said Ms Seif.