CAIRO — Egyptian police fired tear gas and rubber bullets in a second day of clashes Sunday with rock-throwing protesters demanding that the ruling military quickly announce a date to hand over power to an elected government.

Tensions are rising on Egypt's streets in the days leading up to Nov. 28 — the start of the first parliamentary elections since the ouster of authoritarian leader Hosni Mubarak. The violence reflects rising public anger over the slow pace of reforms and apparent attempts by the ruling generals to retain power over a future civilian government.

An estimated 5,000 people protested Sunday in and around Cairo's Tahrir Square, birthplace of the 18-day uprising that toppled Mubarak in February. Many chanted "freedom, freedom" as they pelted police with rocks and a white cloud of tear gas hung in the air.

"We have a single demand: The marshal must step down and be replaced by a civilian council," said protester Ahmed Hani, referring to Field Marshal Hussein Tantawi, head of the ruling military council and Mubarak's longtime defense minister. "The violence yesterday showed us that Mubarak is still in power," said Hani, who was wounded in the forehead by a rubber bullet. He spoke over chants of "freedom, freedom" by hundreds of protesters around him.

In clashes Saturday in Cairo and other major cities, two protesters were killed and hundreds were wounded. The clashes were one of only a few violent confrontations to involve the police since the uprising. The black-clad police were a hated symbol of Mubarak's regime and they have largely stayed in the background while the military took charge of security. There was no military presence in and around Tahrir Square on Saturday or Sunday.

The military, which took over from Mubarak, has repeatedly pledged to hand over power to an elected government but has yet to set a specific date. According to one timetable floated by the army, the handover will happen after presidential elections are held late next year or early in 2013. The protesters say this is too late and accuse the military of dragging its feet. They want a handover immediately after the end of the staggered parliamentary elections, which will take place over the months to come and finish in March.

On Sunday, rocks, shattered glass and trash covered Tahrir Square and the side streets around it. Several hundred protesters were camping out on the lawn of the square's traffic island, and protesters manning barricades into the square checked the IDs of anyone trying to enter.

The windows of the main campus of the American University in Cairo, which overlooks the square, were shattered and stores were shuttered.

"The marshal is Mubarak's dog," read freshly scrawled graffiti in the square.

An Interior Ministry statement said 55 protesters have been arrested since the violence began on Saturday and a total of 85 policemen were hurt in clashes. It said some of the protesters were using firearms, firebombs and knifes to attack security forces.

Yahya el-Sawi, a 21-year-old university student, said he was enraged by the sight of riot police beating up protesters already hurt in an earlier attack by the security forces.

"I did not support the sit-in at the beginning, but when I saw this brutality, I had to come back to be with my brothers," he said.

Many of the protesters had red eyes and coughed incessantly. Some wore surgical masks to ward off the tear gas. A few fainted, overwhelmed by the gas.

Hundreds of protesters gathered near the Interior Ministry, which is in charge of police, to offer the Muslim noon prayers, but came under police attack using tear gas and rubber bullets. Ali Saber, a protester who attended the prayer, said the man who led the prayer was hit in the shoulder by a gas canister.

Doctors staffing two field hospitals in the square said they have treated around 700 protesters so far on Sunday. Alaa Mohammed, a doctor, said most of those treated suffered breathing problems or wounds caused by rubber bullets.

"The police are targeting the head, not the legs as they normally do," said Mohammed.

Protesters were using social networking websites to call on Egyptians to join them, and there were reports of several demonstrations headed to the square, including one from Cairo University.

On Saturday, police fired rubber bullets, tear gas and beat protesters with batons, clearing the square at one point and pushing the fighting into surrounding side streets of downtown Cairo. At least one protester was killed in Cairo, and another in Alexandria, officials said, and 676 were injured.

The government has urged protesters to clear Tahrir Square.

A member of the military council, Maj. Gen. Mohsen el-Fangari, said protesters' calls for change ahead of the election were a threat to the state.

"What is the point of being in Tahrir?" he asked, speaking by phone to a private TV channel. "What is the point of this strike, of the million marches? Aren't there legal channels to pursue demands in a way that won't impact Egypt ... internationally?"

"The aim of what is going on is to shake the backbone of the state, which is the armed forces."

He warned that if the nation's security continues to be breached, the full weight of the law will be implemented against the offenders.

Some of the wounded had blood streaming down their faces and many had to be carried out of the square by fellow protesters to waiting ambulances. Human rights activists accused police of using excessive force.