At least 26 people were killed in Port Said on Saturday in a rampage by protesters angry that a court had sentenced 21 people to death over a soccer stadium disaster that killed 74 last year, state TV reported.
Armored vehicles and military police were deployed on the streets of the Mediterranean city. The state news agency quoted a general as saying the military was sent to "establish calm and stability in Port Said and to protect public institutions."
The ruling followed nine deaths during protests nationwide on Friday and early on Saturday, held to mark two years since Egypt's revolution forced strongman Hosni Mubarak from power and to accuse President Mohamed Morsi and his Islamist allies of re-imposing authoritarian rule.
The judge, Sobhy Abdel Maguid, read out a list of 21 names "referred to the Mufti," a phrase used to denote a death verdict as all such sentences must be reviewed by Egypt's top religious authority.
Seventy-three people have been charged with involvement in the February 1, 2012 disaster at the end of a match between Cairo's al-Ahly and al-Masry, the local team.
Spectators were crushed when panicked crowds tried to escape from the stadium after a post-match pitch invasion by supporters of al-Masry. Others fell or were thrown from terraces, witnesses said.
Many of those who died were supporters of al-Ahly.
The verdicts for others accused will be announced on March 9, said the judge, who had called for calm in the court before and during the reading of the ruling.
In response to the sentences, supporters gathered at al-Ahly club in Cairo cheered. In the courtroom on the outskirts of Cairo, families of victims clapped and some wept with emotion.
"God is greatest" one shouted, while others held up pictures of the victims.
Soccer fans and families of those killed had threatened more violence if the punishments did not satisfy them, and many had demanded the accused be executed.
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