CAIRO, Egypt — It starts off with a single grope, an unfamiliar hand reaching for a buttock, or maybe a breast.

But before there is time to react, the one hand turns into many, grabbing, tearing, stripping, biting — raping.

This is Cairo’s famed Tahrir Square. Once the epicenter of Egypt’s peaceful uprising, where activists plotted an idealistic future, the immense plaza in downtown Cairo is now also something much darker — a hub for mass sexual assaults against female protesters and journalists.

Violent mobs of sometimes hundreds of men have contributed to an uptick in violations against women in the square in recent months, culminating in the highest-ever number of sexual incidents at a protest on the recent Jan. 25 anniversary of Egypt’s uprising. On that day, at least one of the 19 victims was forced to undergo surgery. Her genitals were sliced with a knife, health officials said.

“We’ve experienced and witnessed a lot of … violence happening all over the square,” said Engy Ghozlan, co-founder of Harassmap, a social initiative that uses a text message system to report sexual harassment in Egypt. “The prevalence of the cases is increasing, the viciousness of the cases is increasing. And it’s a phenomenon that is widespread in Tahrir Square.”

The sexual harassment of women of all walks of life has in recent years proliferated on the streets of Cairo, where men catcall, grope or gesture suggestively to Egyptian and foreign women alike. In one instance that received worldwide attention, a group of men attacked CBS News correspondent Lara Logan on Feb. 11, 2011. Logan later said she thought she was going to die at that moment in Tahrir Square.

According to a 2008 study by the Egyptian Center for Women’s Rights (ECWR) — the only report of its kind — 83 percent of Egyptian women and 98 percent of foreign women have experienced sexual harassment in Egypt. Men surveyed in the study told the center the harassment satisfies their sexual desires, or makes them feel more masculine.

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