Several hundreds of Egyptians protested in central Cairo on Monday against a court ruling that sent three leading secular pro-democracy campaigners to jail, witnesses said.
Raising a banner reading "Freedom for all detainees", the protesters chanted against the military-backed government, calling army chief General Abdel Fattah al-Sisi "a dog".
On Sunday a court handed out three-year jail terms for Ahmed Maher, Ahmed Douma and Mohamed Adel, symbols of the uprising that toppled President Hosni Mubarak in 2011, for protesting without permission and assaulting the police.
The European Union urged Egypt on Monday to reconsider the jail sentences.
The government passed a law last month banning protests not authorised by police in an attempt to end demonstrations by Islamists demanding the reinstatement of elected President Mohamed Mursi, who was removed by the army in July.
But the new law prompted more protests led by liberal activists including Maher, Adel and Douma.
The court ruling on Sunday also fined the three 50,000 Egyptian pounds ($7,200) each and ordered them to be put under police supervision for three years after their jail terms end.
"Why is this government so scared of us? Down, down with the military rule," their supporters chanted during Monday's march, which the police took no action to prevent.
One of the demonstrators, Louai Mohamed, said the march was in response to the jailing of the activists. "We will continue our protests and the revolution will continue," he said.
Sisi, who overthrew Mursi following mass protests against his rule, still enjoys wide public support, but his fierce crackdown on Mursi's Muslim Brotherhood and now the punishment of his secular critics has eroded his popularity somewhat.
The government is pursuing a political transition plan that will include a mid-January vote on a new constitution, followed by presidential and parliamentary elections.