A disciplinary hearing has begun in Cairo for two Egyptian judges who said recent elections were fraudulent.
Heavy security has been imposed on the streets
Clashes broke out between riot police and demonstrators supporting the two senior appeals court judges.
A heavy security presence has been out on the streets and security officers prevented people from gathering outside the Judges Syndicate.
Dozens of judges have staged a sit-in at their association headquarters, since the hearing was announced.
On Monday, a judge was injured and 15 demonstrators were arrested when police broke up a protest outside the building.
Judges Hesham Bastawisi and Mahmoud Mekki, who are members of the Court of Cassation, are being disciplined after pressing for an inquiry into alleged fraud in the 2005 elections.
Correspondents say the hearing is expected to result in the two judges losing their jobs.
The elections secured the grip on power of President Hosni Mubarak's National Democratic Party, but they were marked by violence and numerous irregularities.
The judiciary in Egypt is required to supervise elections, but many judges have been angered by what they regard as attempts by the government to exploit them to legitimise fraud.
Through their professional association, judges have issued reports detailing last year's alleged violations.