April 6 Youth Movement staged a satirical protest outside Cairo's top judicial body on Tuesday in response to a lawsuit accusing it of being a terrorist group.
Protesters gathered outside the State Council in Giza's Dokki wearing clown masks, coloured wigs and oversized glasses, holding water guns and balloons. They also hung carnival bunting on the building's gate.
The protest was "an ironic reply" to those who accuse the group of terrorism, group member Amr Ali told Al-Ahram's Arabic news website.
Ex-MP Hamdy Al-Fakharany filed a lawsuit to ban April 6 – which helped initiate calls for the 2011 uprising that toppled longtime autocrat Hosni Mubarak – for being a terrorist organisation. An administrative court has set 19 November for the first hearing in the case.
April 6 is a member of the recently established Revolution Path Front, or "Revolutionaries," which opposes both military rule and the Muslim Brotherhood.
The group's leaders have accused the interim authorities of intolerance to criticism and of suppressing dissent, as under the thirty-year rule of president Mubarak.
The youth group backed Morsi in the 2012 presidential runoff, but later joined protests against his Muslim Brotherhood because they perceived the group to have usurped too much political power. April 6 has also condemned the authorities' use of force against protesters.
Al-Fakharany has accused the group of instigating sedition and receiving foreign funds to serve certain agendas.