CAIRO (AP) -- Egypt's political groups blamed one another on Saturday for one of the year's worst bouts of violence between supporters and opponents of the president's Muslim Brotherhood group.
The powerful Brotherhood said it holds the opposition partly responsible for giving "political cover" to "thugs" who attacked and beat hundreds of the group's members outside its Cairo headquarters.
Opposition groups said President Mohammed Morsi is to blame. They accuse Morsi of polarizing the country and of failing to provide stability nine months after being elected in the country's first free presidential race.
Egypt is reeling from a number of crises, including a diesel shortage that has crippled life for millions, an economic downturn, widespread poverty and a lack of security. The interior ministry, which oversees police, has lost much of its powers since the uprising and many policemen are striking for better pay and protesting what they say is the politicization of the force under Morsi.
Leading opposition figure Mohamed ElBaradei wrote on Twitter that the violence is due to the regime's failure to address root causes of anger.
Protesters vented their frustrations Friday at the doorstep of the Muslim Brotherhood, from which Morsi hails. He is a member of the group's political party. Since the fall of longtime leader Hosni Mubarak in early 2011, the Brotherhood has emerged as the most organized political group, winning all elections at the ballot box.
The violence outside of the Brotherhood's headquarters in the sprawling Cairo neighborhood of Muqattam led to around 175 hospitalizations, including around two dozen serious injuries.
Six Brotherhood offices were also ransacked Friday in different governorates. At least one of the offices was torched, while others were broken into and had computers stolen. Ten of the group's buses were torched after protesters suspected Brotherhood members had been ferried to the site of the clashes.
Hundreds of opposition activists saw Friday as a chance to retaliate against what they say was an attack a week before on protesters. A number of activists had spray painted anti-Brotherhood graffiti at the group's headquarters and they say Brotherhood guards beat them. Journalists there covering a meeting were also slapped and beaten in the skirmish. The Brotherhood said its guards were provoked and acted in self-defense.
Activists are also angry that in December, the Brotherhood forcibly removed protest tents from outside the presidential palace in Cairo and held their own sit-in there. The assault took place amid massive protests against temporary powers the president had issued himself and a push by his Islamist backers to rush a draft constitution to a referendum. Ten people died in those clashes between Morsi's supporters and opponents.
The scene three months later outside the Brotherhood's headquarters was reminiscent of December's clashes, though no deaths were reported on Friday.
Thousands of activists converged near the building and battled Brotherhood supporters with birdshot, rocks, knives, sticks and their fists. Gunshots rang out in the neighborhood.
Muslim Brotherhood Secretary-General Mahmoud Hussein told journalists that some media are falsely portraying what took place as a fight. He says what happened near the group's headquarters was an attack on Brotherhood members by "thugs."
According to Tareq Said, a spokesman for the liberal opposition group al-Tayar al-Shaabi, the Brotherhood is sounding a familiar refrain.
"The Brotherhood is using the same defaming language about the opposition as Mubarak's regime had done, calling them thugs and attackers," he said. "It just proves that we are under a regime that is like Mubarak's."
Before answering reporters' questions, the Brotherhood played video of its members bloodied and bruised, being dragged by angry crowds in the hilly area around its headquarters. One Brotherhood member sat on the stage during the press conference, his face covered in gauze and what appeared to be burns.
"The facts prove that the Brotherhood were attacked, and not the other way around," the group's secretary-general said.
Riot police stood guard around the building during the clashes. They did not interfere to break up the two sides fighting a few blocks away. Later in the evening, the police fired volleys of tear gas at protesters who tried to approach the headquarters.
In the absence of a strong police force, some have accused the Brotherhood of creating its own militias.
Ahmed Aref, a spokesman of the Brotherhood, denied this and said the scene near the group's headquarters would have been different if the allegations were true.
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