PORT SAID/CAIRO – At least 32 people were killed on Saturday when Egyptians rampaged in protest at the sentencing of 21 people to death over a soccer stadium disaster. The violence compounds the political crisis facing Islamist President Mohamed Morsi.

Armored vehicles and military police fanned through the streets of Port Said, a city of some 600,000 people, where gunshots rang out and protesters burned tires in anger that people from their city had been blamed for stadium deaths last year.

The rioting in Port Said, one of the most deadly spasms of violence since Hosni Mubarak’s ouster two years ago, followed a day of anti-Morsi demonstrations on Friday, when nine people were killed. The toll over the past two days stands at 41.

The flare-ups make it even tougher for Morsi, who drew fire last year for expanding his powers and pushing through an Islamisttinged constitution, to fix the creaking economy and to cool tempers enough to ensure a smooth parliamentary election.

That vote is expected in April and is meant to cement a democratic transition that has been blighted from the outset by political rows and street clashes.

The National Defense Council, led by Morsi and which includes the defense minister who commands the army, called for “a broad national dialogue that would be attended by independent national characters” to discuss political differences and ensure a “fair and transparent” parliamentary poll.

The statement was made on state television by Information Minister Salah Abdel Maqsoud, who is also on the council.

The National Salvation Front of liberal-minded groups and other opponents cautiously welcomed the call but demanded any such dialogue have a clear agenda and guarantees that any deal would be implemented, spokesman Khaled Dawoud told Reuters.

The Front spurned previous calls for dialogue, saying Morsi ignored voices beyond his Islamist allies.

The Front earlier on Saturday threatened an election boycott and to call for more protests on Friday if demands were not met.

Its demands included picking a national unity government to restore order and holding an early presidential poll.

A judge announced the death penalty on Saturday for 21 of the 73 defendants on trial for the Port Said massacre. Clashes in Port Said following the announcement of the verdict left at least nine dead and dozens more injured, according to the Egyptian daily Al- Ahram.

Seventy-four people died in riots at a soccer stadium in Port Said on February 1, 2012. Eyewitnesses said police did nothing to stop the melee that broke out between rival soccer teams and even refused to open the doors to allow people to escape. The massacre was held up as proof of the country’s slide toward anarchy.

Over the past week, the “ultras,” or young soccer hooligans who are often at the head of protest marches and responsible for much of the violence at Egypt’s protests posted online threats promising to destroy and burn buildings across Cairo if they were unsatisfied with the verdict.

If it is anything less than capital punishment, “the country will burn,” one 19-year-old ‘ultra’ named Ahmed told The Jerusalem Post on Friday in Tahrir Square.

“We are angry because we haven’t received our rights... It’s not just a football match, the [Muslim] Brotherhood wants to continue to burn the country to they can continue to rule,” he said. “There’s no justice.”

In the aftermath of clashes on Friday night to mark the two-year anniversary of the revolution, pundits and politicians focused much attention on a new group of protesters who also could be linked to the ultras: the black bloc.

For the first time on Friday, teenagers and young people came out in force dressed head-to-toe in black, many wearing black ski masks.

The term “black bloc” began in Germany in the 1970s with a group of anarchists and has been used loosely in a number of other instances since then, including at the anti-World Trade Organization protests in Seattle in 1999 and the G20 summit in Toronto in 2010.

In Egypt, members of the black bloc refused to speak to the media.

“No one knows anything about them, they appeared three or four days ago,” said Adel, an Arabic literature teacher who saw them in Tahrir Square on Friday for the first time. “Some people think they are ‘ultras,’ but they issued a statement on Friday saying ‘we’re not ultras, we’re not anyone.’” However, some wore ski masks with the insignia of the Al Ahly soccer team.

Many seasoned activists dismissed the black blocs as angry teenagers looking to stir up trouble, who will not have a lasting impact.

“We might see a reemergence [in coming protests], but I don’t expect them to hijack the revolution,” said Adel.

“[Are the black bloc] anarchist revolutionaries or 18 year olds who live with their moms & wear black masks thinking life is a video game?” one activist asked sarcastically on Twitter.