Egypt has started the trial of former top officials accused of sending men on horseback and camels to attack protesters on one of the most violent days of the uprising that toppled Hosni Mubarak, the ex-president, in February.
Among the 25 people on trial are Safwat al-Sharif, the former head of parliament's upper house who was a longtime confidant of Mubarak, and Fathi Sorour, former speaker of the lower house.
All those appearing in court on Sunday denied the charges filed against them.
After the first day of the trial was televised, Judge Mustafa Hassan Abdullah said live broadcasts of
future hearings would be banned, except for the session in which the verdict would be pronounced.
A fact-finding judicial committee ruled in July that al-Sharif masterminded the February 2 assault that left several protesters dead. Horse and camel riders stormed into Tahrir Square, the epicentre of the revolution, attacking protesters with whips and swords. Clashes between opponents of Mubarak and his loyalists ensued.
Tantawi hearing postponed
Separately on Sunday, the testimony of Egypt's military ruler in the trial of Mubarak was postponed.
Field Marshal Hussein Tantawi had been expected to offer highly anticipated testimony about Mubarak's alleged role in the killing of protesters in the uprising.
Assem Qandil, a defence lawyer, said Tantawi was unable to testify because he was busy dealing with security issues after the Israeli embassy was attacked on Friday.
Qandil said the field marshal had offered to send written testimony, but "the judge refused and reissued a request for Tantawi to show up in court".
Egyptian state television said Tantawi had now been ordered to give his testimony on September 24 or 25.
Tantawi, who was Mubarak's defence minister during the uprising in January and February, is the leader of the military council which was handed power when Mubarak stepped down.
Mubarak is charged with ordering the killing of anti-government protesters but denies the charges against him.
Nearly 900 people were killed in the unrest which lasted for 18 days.