Female protesters gathered in downtown Cairo on Thursday demanding an investigation into the deaths of activist Shaimaa Sabbagh and others they say were killed by Egyptian security forces around the anniversary of the 2011 uprising. Sabbagh was killed during a march on the eve of the Jan. 25 anniversary and another 25 - men and women - were killed on Sunday in demonstrations commemorating the onset of the popular revolt that toppled veteran autocrat Hosni Mubarak. The protesters assembled at the site of Sabbagh's death near Cairo's Tahrir Square, chanting "The interior ministry are thugs!" and holding signs with the word "Murderer" scrawled over Interior Minister Mohamed Ibrahim's face. About 100 had gathered at the time the demonstration was meant to start at 2.00 pm local time, and protesters appeared to be avoiding blocking the streets by staying on sidewalks. A number of men stood across the street alongside police officers, making lewd hand gestures and calling the protesters "dogs" and other profanities. One of the rally's organizers said they had called for only women to attend because they feared the protests being infiltrated by plainclothes security agents. Street unrest has revived despite President Abdel Fattah al-Sisi's crackdown on dissent, whether Islamist or liberal, in the wake of the military's overthrow of elected Islamist president Mohamed Mursi in 2013, when Sisi headed the armed forces.