At least 30 people have died in rioting in Port Said in Egypt after a court announced death sentences for 21 people for their role at a fatal football match.
In February last year, 74 people were killed after a match between Al Ahly of Cairo and the Suez team al-Masri.
Many of those killed were from the visiting team's supporters. al-Masry fans invaded the pitch, hurling stones and fireworks at visiting supporters from the Cairo club.
A section of al-Ahly supporters, known as the "ultras", played a prominent role in the protests against ex-President Mubarak.
Families of the dead cheered when the judge announced the ruling on Saturday.
However, the ruling caused supporters of the defendants to go on a rampage in Port Said. Two police officers were shot dead outside the city's prison.
At least another 24 people were killed and about 300 were wounded in further clashes, officials said.
The Mena news agency reported two footballers were among those killed.
Seventy-three people, including nine policemen, were tried over the stadium clashes. None are al-Ahly fans.
The judge said he would announce verdicts for the remaining defendants on 9 March.
Thousands of people took to the streets on Friday the second anniversary of the fall of President Hosni Mubarak to voice their opposition to his successor, President Mohammed Mursi, accusing him of betraying the revolution.
At least seven people were killed and more than 450 wounded in unrest across Egypt.