CAIRO, Egypt — The attackers used knives, fireworks and scarves to kill, maim and strangle their rival soccer fans. Others, according to eyewitnesses interviewed by GlobalPost, threw spectators from the stadium's highest seats and onto the concrete below.

These horrific scenes were relayed to GlobalPost by a handful of residents from the Suez canal town of Port Said, which on Wednesday hosted a soccer match that descended into the worst sports-related violence in Egypt's history and left at least 74 dead.

But how did what seems on its face to be a bad case of soccer hooliganism gone awry evolve into a far-reaching political crisis for Egypt's ruling generals?

The massacre at the game — featuring traditionally antagonistic teams and fans of the Al-Ahly soccer club, notorious for having mobilized in political protests against police — has kicked off a new wave of clashes between protesters and security forces in downtown Cairo and the city of Suez overnight.

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Nearly 1,000 have been injured by tear gas and rubber bullets in Cairo, health officials said, and least two protesters were shot dead in Suez. Anti-police and government marches are already converging on Cairo's iconic Tahrir Square this afternoon — where police battle demonstrators through thick clouds of tear gas and parliament met Thursday to address the incident.

Because Al-Ahly fans, known as "Ultras," played a key role in both the uprising and post-revolt protests by turning out in large numbers to bolster demonstrators, secure Tahrir, and chant against the military, speculation runs high that Egypt's already embattled police force has it out for the soccer fans.

The fresh protests targeting police at Egypt's ministry of interior sprung from damning video and eyewitness testimony describing dozens of riot police stationed at the Port Said stadium — and that normally tightly control Egypt's soccer games — standing by while attackers from the Al-Masry team's bleachers rushed the field with weapons and ambushed Al-Ahly players and fans on the field and in the stadium seats.

"The invasion of people toward the field began with the final whistle of the referee," said Mohamed Said Mosleh, a 30-year-old engineer from Port Said who attended the game, sitting on the Al-Masry side. "The police never tried to stop anyone. This has never happened before."

Spectators and fans said they found stadium gates uncharacteristically locked as they tried to flee the onslaught — and many either suffocated or were crushed in a stampede of bodies scrambling for the exits, the ministry of health said.

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In the middle of the melee, someone shut off the stadium lights, plunging the crowd into darkness.

"Some of the Ahly fans ran to the top of the bleachers to try to escape and, they were thrown off," said Hatem Omar, 45, a perfume vendor and resident of Port Said. He also watched the tragedy unfold from the Al Masry bleachers.

"Some of the Ahly fans ran toward the gates. They were locked and they became trapped," Omar said.

The police inaction has given rise to a myriad of charges and theories of who is to blame amid the battle for Egypt's future in the year since protesters overthrew former Egyptian President Hosni Mubarak.

Many, both in Cairo and Port Said, believe the tragedy at the soccer stadium was engineered by the council of army generals that seized power last year, in a last-ditch effort to reinstate martial law as anti-regime protests grow and a newly-elected parliament asserts its influence.

Egypt's so-called "emergency law," which has existed in one form or another for decades, gives police and army sweeping powers of detention and arrest. The law was partially lifted by de-facto leader Field Marshal Mohammed Tantawi, ahead of protests planned for the first anniversary of the beginning of the uprising on Jan. 25 this year.

On Thursday, soccer fans chanted, "This is not football chaos, this is a military massacre," as they charged through Cairo's streets in mass marches.

"I believe this was something planned from the beginning," Omar said. Mosleh also said he suspected police had a hand in at least facilitating the violence, after he and his peers complained to stadium police about the lack of security at the game and were dismissed by the officers.

But whether or not the deadly clashes were a sinister regime plan or just negligence on the part of a demoralized and ambivalent police corps, the Port Said massacre and the impassioned, violent response underscore the grave challenges facing Egypt as it struggles to stabilize following years of authoritarian rule.

Little if any effort has been made to reform the ministry of interior, which was at the heart of Mubarak's oppressive police state and which presided over the widespread torture of everyday citizens for decades, security experts here said.

"Each individual policeman, psychologically speaking, they are still very, very angry that they were beaten and defeated by the Egyptians, by the people," said Amir Salem, a human-rights lawyer and author of several books on Egypt's police.

The military's lack of transparency in its tenure as caretaker government has nurtured a near-universal tendency to blame daily-life events on deliberate acts of sabotage — whether by the regime itself, foreign spies or "thugs" seeking to sow chaos.

“I don't talk to anyone who is from outside Egypt or wants to destroy our country," one policeman snapped recently in the Cairo neighborhood of Rod El-Farag. "We are exposed to spies and thugs everywhere."