The retrial of former Egyptian leader Hosni Mubarak has been plunged into chaos after the judge quit on the first day.
Mubarak returned to court on Saturday to face a new trial over the deaths of 800 protests during the 2011 revolt that led to him being ousted.
But Judge Mustafa Hassan Abdullah said he had decided to refer the case to the Cairo appeals court because he felt "unease" in reviewing it.
Sky's Tom Rayner said Mr Abdullah also blamed health problems and suggested he did not want to embarrass himself - which may be connected to his sympathies with the Mubarak regime.
A man calls for Mubarak to face a court in the HagueAs he filed out of the courtroom after a hearing that lasted just seconds, there was uproar with people shouting and waving their arms.
Civil society lawyers attending the trial chanted: "The people want the execution of the president."
Last October, the same judge acquitted the defendants in the infamous "Battle of the Camels" trial, who were accused of sending men on camels and horses to break up a protest during the 2011 uprising.
"This judge and this circuit acquitted all the defendants in the battle of the camels and there is a lot of doubt over their position. This prevents him from conducting this trial," said Amir Salem, a lawyer for the victims of families.
There was uproar in the courtroom as the judge walked outMubarak is facing retrial on charges of complicity in the murder of more than 800 protesters killed during the revolt.
Last year, he was sentenced to life imprisonment on the same charges, which include indictments related to corruption.
But the conviction was overturned due to failings in the prosecution case after a successful appeal in January.
He will now face those charges again, alongside his former interior minister Habib El Adly and four aides.
The findings of an independent fact-finding report, leaked to the Guardian newspaper, may bolster some of the evidence against him.
It indicates that Mubarak and other senior officials may have had knowledge or been complicit in the widespread use of torture and killings by the regime's forces during the height of the revolution.
Some families of the victims gathered outside courtEarlier on Saturday, television footage showed Mubarak, dressed in white and wearing sunglasses, wheeled out of an ambulance on a stretcher and taken into the capital's Police Academy in a suburb of the capital for the hearing.
In the courtroom, he was seen sitting up, smiling and waving from inside a barred cage before the proceedings were adjourned.
He was flown in from a military hospital where he is being treated.
The 84-year-old has suffered several health scares and the official news agency MENA even reported him clinically dead at one point as he slipped into a coma.
Outside the compound, pro-Mubarak demonstrators outnumbered opponents with the two groups kept apart.
Relatives of victims of Mubarak's security forces held posters of young men killed in the revolt.
"What can I expect from this trial? If there was justice in this country, the first trial would have been fair," said Eman Saeed, whose 24-year old son Mohab died in January 2011 after marching to Tahrir Square
Until Saturday's courtroom turmoil, the fate of the ousted strongman has been largely eclipsed by deadly violence and economic woes currently gripping Egypt.
Mohammed Morsi's presidency has been plagued by unrest and deadly clashes between protesters and police, a revolt in the canal cities, sectarian violence and a devastating economic crisis.