Families of those killed in the Egyptian crackdown on protesters during the unrest that led Hosni Mubarak to relinquish power, have clashed with police outside a Cairo court.
They pelted a convoy of security vehicles with stones as they ferried the former interior minister and six ex-ministers to trial.
Habib al-Adli and others are charged with killing pro-democracy demonstrators in the uprising which claimed 840 lives.
Adli is despised in Egypt for his hard line tactics during the first days of the revolt as police laid into anti-Mubarak supporters with batons, teargas, water canon and live rounds.
The court session was postponed and a new date set for July 25.
Former president Hosni Mubarak goes on trial on August 3.