Hundreds of people throwing petrol bombs and rocks attacked the national headquarters of Morsi's Muslim Brotherhood.
The Egyptian phase of the Arab Spring seems to have hit one of those "bumps in the road". The road is tyranny and the bump is a large number of Egyptians uninterested in letting Morsi do to Egypt what Erdogan did to Turkey.
At least five people were killed in Egypt and nearly 200 wounded on Sunday in clashes between supporters and opponents of Islamist President Mohamed Morsi, security and medical sources said.
In Cairo and Alexandria, more than one million demonstrated.
Hundreds of people throwing petrol bombs and rocks attacked the national headquarters of Morsi's Muslim Brotherhood. The building caught fire as guards and protesters exchanged gunfire.
Waving national flags and chanting "Get out!", a crowd of more than 200,000 had massed by sunset on Cairo's central Tahrir Square in the biggest demonstration since the 2011 uprising that overthrew Morsi's predecessor, Hosni Mubarak.
"The people want the fall of the regime!" they shouted, echoing the Arab Spring rallying cry that brought down Mubarak.
The Tahrir Square crowd roared with approval as an army helicopter hovering overhead dropped Egyptian flags on the protesters. A military source said the move was intended to promote patriotism and was not a gesture of political support.
Southern Egypt saw deadly attacks on anti-Morsi protests. A protester was shot to death in Beni Suef outside the offices of the Brotherhood's Freedom and Justice Party. Gunmen on a motorcycle opened fire on a protest, killing one person and wounding four others in the city of Assiut.
The enraged protesters then marched on the nearby local Freedom and Justice offices, where gunmen inside opened fire, killing two more, security officials said, speaking on condition of anonymity because they weren't authorized to talk to the press. Clashes erupted with protesters and security forces fighting side by side against Morsi's supporters.
There are reports of police and soldiers at the protests which suggests that Morsi doesn't have much on his side except his Islamist militias and any Hamas members who can get there in time to help.
A week ago, with the public sense of worry growing over the upcoming confrontation, Defense Minister Gen. Abdel-Fattah el-Sissi demanded the president and his opponents reach a compromise. He warned that the military would intervene to prevent the nation from entering a "dark tunnel."
Welcome to democracy.
The opposition protests emerge from a petition campaign by a youth activist group known as Tamarod, Arabic for "Rebel." For several months, the group has been collecting signatures on a call for Morsi to step down.
On Saturday the group announced it had more than 22 million signatures -- proof, it claims, that a broad sector of the public no longer wants Morsi in office.
It was not possible to verify the claim. If true, it would be nearly twice the around 13 million people who voted for Morsi in last year's presidential run-off election, which he won with around 52 percent of the vote.
"Mubarak took only 18 days although he had behind him the security, intelligence and a large sector of Egyptians," said Amr Tawfeeq, an oil company employee marching toward Ittihadiya with a Christian friend. Morsi "won't take long. We want him out and we are ready to pay the price."