Egypt’s presidency held the political forces responsible for the clashes that erupted Friday outside the presidential palace in Cairo between protesters and the security forces, Egyptian state TV reported."These violent, vandalistic acts have nothing to do with any legitimate political practices of peaceful expression of opinion,” the statement said. The presidential statement also urged the political forces to denounce the violence committed outside the presidential palace and to call their supporters to immediately leave the area. The statement addressed the political forces "that might have instigated” such acts, stating there will be investigation into the aggression committed by protesters against the security forces at the palace.”The security forces will act strictly to apply the law and protect the country’s institutions,” the statement said.Witnesses told Xinhua that clashes erupted Friday evening near the presidential palace in Heliopolis, Cairo, when a number of protesters threw Molotov cocktails and fireworks in the direction of the palace while the security members responded with massive water hoses and tear gas bombs.The Health Ministry said the number of people injured during the protests nationwide was 30 so far, according to official reports, most of whom were during the clashes outside the presidential palace.”Only one was injured in Port Said and it was due to pushing crowds,” Abdel-Rahman Farag, head of Port Said hospitals, said.In response, Egypt’s main opposition bloc the National Salvation Front (NSF) issued a statement stating "clear and explicit denouncement of the acts of violence and the aggression against the public and private properties,” reaffirming commitment to peacefulness of demonstrations. The NSF statement, in turn, held President Mohamed Morsi and his main supporters, the Muslim Brotherhood (MB) responsible for the tension prevailing among Egyptians over the past two months, referring to their division over the newly-drafted controversial constitution that was supported by Morsi and opposed by many political forces.Thousands of Egyptians nationwide took to public squares Friday to protest against the current government in commemoration of the victims of a football riot tragedy that killed 74 fans in the seaside city of Port Said at the same time last year. Agencies