400 hurt in Cairo rally protesting deaths at soccer riot Updated at 5:20 p.m. ET: Anger over a deadly soccer riot erupted into fresh clashes that injured nearly 400 people in Cairo on Thursday as security forces fired tear gas at fans and other protesters who accused police of failing to stop the bloodshed. The violence, which comes as security has been steadily deteriorating, threatened to plunge the country into a new crisis nearly a year after a popular uprising forced former leader Hosni Mubarak to step down, The Associated Press reported. A network of rabid soccer fans known as Ultras vowed vengeance, accusing the police of intentionally letting rivals attack them after Wednesday's Egyptian league match in the seaside city of Port Said because they have been at the forefront of protests over the past year, first against Mubarak and now the military that assumed power after his Feb. 11 ouster. What began Thursday as a peaceful march from the Al-Ahly headquarters in Cairo descended into fury as more than 10,000 protesters reached the area outside the Interior Ministry building near Tahrir Square, the epicenter of last year's popular uprising that ousted Mubarak. Protesters set tires on fire, sending black smoke in the air. Motorcycle drivers ferried some of those wounded from the site as ambulances were unable to get through. The Health Ministry said in all 388 were injured, most from tear gas inhalation as well as bruises and broken bones from rocks that were thrown. Updated at 4:45 a.m. ET: Egypt's prime minister dissolves the Egyptian Soccer Federation's board and refers its members for questioning by prosecutors after post-match clashes that left 74 dead, The AP reports. Published at 3 a.m. ET: CAIRO -- The head of Egypt's ruling military council, Field Marshal Mohamed Hussein Tantawi, vowed Thursday to track down those behind soccer violence that killed at least 74 people in Port Said, speaking in a rare phone call to an Egyptian TV channel. PhotoBlog: Chaotic scenes as injured soccer fans return to Cairo