(CNN) -- Dozens of demonstrators demanding the revocation of a new protest law clashed with Egyptian security forces in Cairo Tuesday, igniting a firestorm of criticism online and on the streets, state media and activist reported.
Police fired water cannon and tear gas canisters to disperse two small demonstrations, one against the military trials of civilians and another in honor of a man killed by police last year.
"Riot police began pulling and pushing everybody, beating us with sticks, grabbing hair, and dragging people. Immediately afterwards, tear gas was fired. I actually couldn't breathe because the gas was so intense. I started running and I saw some people were being arrested," activist Gigi Ibrahim told CNN as she described how nearly 200 riot gear clad police officers broke up a demonstration she attended that had around 100 people.
Prominent youth activists refused to abandon colleagues detained by the security forces and instead voluntarily surrendered to authorities in a show of solidarity. The group included founders of the group No to Military Trials, journalists, and a human rights lawyer.
"People gathered in front of the Shura Council in central Cairo in violation of the protest law. The security apparatus immediately issued a warning to demonstrators but they did not comply and threw rocks and bricks at the police." an Interior Ministry statement said, adding that 28 people were detained.
Police later dumped more than a dozen of the female detainees along an empty highway after beating and harassing the group for several hours, several witnesses and activists reported Tuesday.
"We were thrown in the desert, our friends found us and we are all ok. F*** scaf (Supreme Council of the Armed Forces) and f*** the police," Salma Saed, one of the activists arrested, tweeted upon her release.
The crackdown on some of Egypt's most recognizable dissident figures comes just one day after the military-backed government announced the implementation of a new protest law that requires organizers seek permission from authorities before gathering.
"If the police and the government are not getting this message, we can protest every day for the rest of our lives because there are so many people who gave their lives for the right to protest. We gained this right to protest so there is no way we can go back. It is impossible." Ibrahim said.