CAIRO — Thousands of opponents of Egypt's Islamist president clashed with his supporters in cities across the country Friday, burning several offices of the Muslim Brotherhood, in the most violent and widespread protests since Mohammed Morsi came to power, sparked by his move to grant himself sweeping powers.
The violence, which left 100 people injured, reflected the increasingly dangerous polarization in Egypt over what course it will take nearly two years after the fall of autocrat Hosni Mubarak.
Critics of Morsi accused him of seizing dictatorial powers with his decrees a day earlier that make him immune to judicial oversight and give him authority to take any steps against threats to the revolution.
On Friday, the president spoke before a crowd of his supporters massed in front of his palace and said his edicts were necessary to stop a minority that was trying to block the goals of the revolution.
There are weevils eating away at the nation of Egypt, he said, pointing to old regime loyalists he accused of using money to fuel instability and to members of the judiciary who work under the umbrella of the courts to harm the country.
Clashes between his opponents and members of Morsi's Muslim Brotherhood erupted in several cities. In the Mediterranean city of Alexandria, anti-Morsi crowds attacked Brotherhood backers coming out of a mosque, raining stones and firecrackers on them. The Brothers held up prayer rugs to protect themselves and the two sides pelted each other with stones and chunks of marble, leaving at least 15 injured. The protesters then stormed a nearby Brotherhood office.
State TV reported that protesters burned offices of the Brotherhood's political arm in the Suez Canal cities of Suez, Ismailia and Port Said, east of Cairo.
In the capital Cairo, security forces pumped volleys of tear gas at thousands of pro-democracy protesters clashing with riot police on streets several blocks from Tahrir Square and in front of the nearby parliament building.
Tens of thousands of activists massed in Tahrir itself, denouncing Morsi and chanting Leave, leave and Morsi is Mubarak ... Revolution everywhere. Many of them represented Egypt's upper-class, liberal elite, which have largely stayed out of protests in past months but were prominent in the streets during the anti-Mubarak uprising that began Jan. 25, 2011.
We are in a state of revolution. He is crazy if he thinks he can go back to one-man rule, one protester, Sara Khalili, said of Morsi.
Frustration had been growing for months with Morsi, Egypt's first freely elected president, who came to office in June. Critics say the Muslim Brotherhood, from which he hails, has been moving to monopolize power and that he has done little to tackle mounting economic problems and continuing insecurity, much less carry out deeper reforms.
Morsi's supporters, in turn, say he has faced constant push-back from Mubarak loyalists and from the courts, where loyalists have a strong presence.
Morsi made his move Thursday, at a time when he was bolstered by U.S. and international praise over his mediating of a cease-fire ending a week of battles between Israel and Hamas in Gaza. Only a day earlier, Morsi had met with U.S. Secretary of State Hillary Rodham Clinton just before the truce was announced.
U.S. State Department spokeswoman Victoria Nuland said Friday that Morsi's declarations raise concern for many Egyptians and for the international community.
In Israel on Friday troops fired on Gazans surging toward Israel's border fence, killing one person but leaving intact the fragile two-day-old cease-fire between Hamas and the Jewish state.
The truce, which calls for an end to Gaza rocket fire on Israel and Israeli airstrikes on Gaza, came after eight days of cross-border fighting.
Hundreds of Palestinians approached the border fence Friday in several locations in southern Gaza, testing expectations Israel would no longer enforce a 300-yard-wide no-go zone on the Palestinian side of the fence that was meant to prevent infiltrations into Israel. In the past, Israeli soldiers routinely opened fire on those who crossed into the zone.
In one incident captured by Associated Press video, several dozen Palestinians, most of them young men, approached the fence, coming close to a group of Israeli soldiers standing on the other side.
Some Palestinians briefly talked to the soldiers, while others appeared to be taunting them with chants of God is Great and Morsi, Morsi, in praise of Egyptian President Mohammed Morsi, whose mediation led to the truce.