Football Fans of Egyptian club Al-Ahly stormed the country's Soccer Federation headquarters in Cairo and set it on fire after a court acquitted seven of nine police officials on trial for their alleged role in the Port Said stadium riot last year which claimed 74 lives and left 1,000 people injured.
Earlier on Saturday, a Cairo court confirmed the death sentences given to 21 football fans for their parts in the riot which is said to be the worst football disaster in the north African country
Fire also swept through a nearby police club, but it was not immediately clear whether Al-Ahly fans who are also known as ''ultras'' were responsible for that blaze as well.
Heavy black smoke billowed out of the rose-colored, three-story neocolonial building of the Egyptian soccer federation in central Cairo.
The court also sentenced two senior police officers to 15 years in prison, but acquitted the other seven security officials.
Thousands of the club's fans had gathered to welcome the death penalty verdicts, mostly given to fans of rival club Al-Masry, who started the riot. They also protested against the police acquittals.
In a ruling shown on live television, the Cairo court also sentenced five more people to life in jail for their roles in the riot and acquitted 28.
The remaining defendants received shorter jail sentences of between one to 15 years.
The court also sentenced the city's former security chief, Major General Essam Samak, to 15 years in prison.
Samak was the most senior of the nine security officials tried for their part in the riot.
Those sentenced to death, mostly fans of Port Said's Al-Masry club, will be hanged.
The case has provoked deadly clashes in the Suez Canal city. Some 40 people died in riots after the death sentences were first announced on January 26, many shot by police.
Many residents of Port Said, which is located on the Mediterranean at the northern tip
of the Suez Canal, have seen the trial as unjust and politicised.
Football fans in the city have felt that authorities were biased in favor of Al-Ahly, Egypt's most powerful club.
The final whistle of the match between Al-Masry and Al-Ahly on February 1 last year prompted more than 13,000 home fans, armed with knives, iron bars and machetes, to storm the pitch and attack rival Al-Ahly players and their 1,200 supporters.
Authorities shut off the stadium lights after the game, plunging it into darkness.
In the exit corridor, the fleeing crowd pressed against a chained gate until it broke open. Many were crushed under the crowd of people trying to flee.
Others fell or were thrown from terraces. It was Egypt's worst football disaster.
Meanwhile, in Port Said, a city that has for weeks been in open rebellion against the government of Islamist President Mohammed Morsi, several hundred people, many of them relatives of the defendants, gathered outside the local government offices to vent their anger.
Port Said has been the centre of the heaviest violence in the latest wave of unrest, which began on January 25, when hundreds of thousands across the country marked the second anniversary of the start of the uprising that toppled Hosni Mubarak's regime two years ago.
The unrest has underlined worsening security in Egyptian cities since the 2011 overthrow of Mubarak, said the Associated Press.
The Islamist government of President Mohamed Mursi is struggling to halt the slide in law and order, hampered by a strike by some protesting police.
At least eight people have been killed in Port Said this week, including three policemen.