A soccer fan is seen near a police car, which was set on fire by fireworks, during clashes between soccer fans and security forces in front of a stadium on the outskirts of Cairo February 8, 2015. [Photo/Agencies]

Egypt's hard-core soccer fans, known as Ultras, frequently clash with police inside and outside of stadiums. They are deeply politicized and many participated in the country's 2011 uprising that forced out President Hosni Mubarak. Many consider them as one of the most organized movements in Egypt after the Islamist Muslim Brotherhood, which the government later outlawed as a terrorist organization following the 2013 military overthrow of Islamist President Mohammed Morsi.

The deadliest riot in Egypt soccer history came during a 2012 match when Port Said's Al-Masry team hosted Cairo's Al-Ahly. That riot, at the time the deadliest worldwide since 1996, killed 74 people, mostly Al-Ahly fans.

Two police officers later received 15-year prison sentences for gross negligence and failure to stop the Port Said killings, a rare incident of security officials being held responsible for deaths in the country. Seven other officers were acquitted, angering soccer fans who wanted more police officers to be held accountable for the incident and other episodes of violence.

In response, angry fans burned down the headquarters of Egypt's Football Association, also protesting its decision to resume matches before bringing those behind that 2012 riot to justice. They've also protested and fought officers outside of the country's Interior Ministry, which oversees police in the country.