Tear gas rises as protesters clash again with riot police near Cairo's Tahrir Square, and opponents of President Mohamed Mursi rally for a day of mass action.<br/> <br />Many in the country are angry following a decree by President Mursi last week that prevents legal challenges to any decision he makes until a new parliament is elected.<br/> <br />The opposition, accusing Mursi of appointing himself a modern-day Pharaoh, is pressing ahead with Tuesday's protest to demand the scrapping of the decree.<br/> <br />Demonstrators have camped out in Tahrir Square since the decision was announced last week, and violence has flared repeatedly.<br/> <br />Tuesday saw fighting gathering momentum on side streets near Tahrir Square as police fired tear gas at protesters, and stones were thrown in response.
