More than 60 people were killed in Egypt this weekend in clashes surrounding the third anniversary of the uprising that ousted Hosni Mubarak. Thousands of people turned out in Cairo’s Tahrir Square, the epicenter of the revolution. But fighting broke out between supporters of the Muslim Brotherhood and state forces, as well as backers of the military government that ousted the Brotherhood from power last year. Some 1,000 people were detained by Sunday night. In a sign of growing activity by militants, an Egyptian army helicopter was shot down in the Sinai desert, killing all five soldiers on board. The group Ansar Beit al-Maqdis has claimed responsibility. Six people were also killed in a series of bombings around Cairo. Following the weekend’s violence, the military government said it would hold presidential elections earlier than its political roadmap had called for, before the races to select a new parliament. Egyptian military leader General Abdel Fattah el-Sisi, who led the coup that overthrew President Mohamed Morsi, is widely expected to run.