Egypt's police on Monday said it arrested four April 6 members who were organising a stand to commemorate their deceased colleague Ahmed El-Masry, Al-Ahram’s Arabic website reported.
A statement on the group's Facebook page, however, says "around 30" of their members have been arrested, including leading members Mohamed Kamal and Ramy El-Sayed.
The police dispersed the stand in Cairo's Boulaq El-Dakrour district, where El-Masry's family resides, as the group did not have a pre-approved request to organise their demonstration.
A protest law, passed last November, mandates that protesters should apply for a protest request from the country's interior minister before organising protests. Violators face hefty fines and prison sentences.
El-Masry was shot dead exactly one year ago while covering the police's dispersal of a Muslim Brotherhood protest in Giza's Mohandiseen.
April 6 Youth Movement, once a celebrated revolutionary group after the 2011 uprising, is now criticised and accused of having ties with ousted Mohamed Morsi's group, the Muslim Brotherhood. The Brotherhood was dubbed a terrorist organisation late last year.
In May, an Egyptian court banned the April 6 movement, one of the youth groups that led the 2011 uprising against autocrat Hosni Mubarak. The ruling stemmed from a private lawsuit accusing the group of defaming the country and colluding with foreign parties.
April 6 had opposed Islamist president Morsi and supported his ouster last summer, but also spoke out against the interim authorities that replaced him, protesting their crackdown on dissent. The group has frequently accused the interim leaders of quashing freedoms and giving the police a free rein.