CAIRO - Egypt's most prominent democracy advocate took up a bullhorn Sunday and called for President Hosni Mubarak to resign, speaking to thousands of protesters who defied a curfew for a third night. Fighter jets streaked low overhead and police returned to the capital's streets - high-profile displays of authority over a situation spiraling out of control.

Nobel Peace laureate Mohamed ElBaradei's appearance in Tahrir, or Liberation, Square underscored the jockeying for leadership of the mass protest movement that erupted seemingly out of nowhere in the past week to shake the Arab world's most populous nation.

Now in their sixth day, the protests have come to be centered in the square, where demonstrators have camped since Friday. Up to 10,000 protesters gathered there Sunday, and even after the 4 p.m. curfew, they numbered in the thousands, including families with young children, addressing Mubarak with their chants of "Leave, leave, leave."

"You are the owners of this revolution. You are the future," ElBaradei told the crowd after nightfall. "Our essential demand is the departure of the regime and the beginning of a new Egypt in which every Egyptian lives in virtue, freedom and dignity."

In a further sign of Mubarak's teetering position after three decades in power, his top ally - the United States - called for an "orderly transition to democracy."

Asked if Washington supports Mubarak as Egypt's leader, Secretary of State Hillary Rodham Clinton avoided a direct answer, telling Fox News: "We have been very clear that we want to see a transition to democracy, and we want to see the kind of steps taken that will bring that about."

German Chancellor Angela Merkel urged the Egyptian government to implement democratic reforms and stop violence against protesters.

Israeli Prime Minister Benjamin Netanyahu told his Cabinet that he was "anxiously following" the crisis, saying Israel's three-decade-old peace agreement with Egypt must be preserved.

Protesters have shrugged off Mubarak's gestures of reform, including the sacking of his Cabinet and the appointment of a vice president and a new prime minister - both seen as figures from the heart of his regime.

ElBaradei, the former head of the U.N. nuclear watchdog agency, has gained a following among young secular democracy activists with his grassroots organizing. But some demonstrators dismiss him as an expatriate long removed from Egypt's problems.

"Many people feel he loves prizes and traveling abroad," said Muhammad Munir, 27. "He's not really one of the people."

The outlawed Muslim Brotherhood, which wants to establish an Islamist state in Egypt, has made some statements that it was willing to let ElBaradei act as point man for the movement. But it also appeared to be moving for a more prominent role after lying low when the protests first erupted.

On Sunday evening, the presence of overtly pious Muslims in the square was conspicuous, suggesting a significant Brotherhood representation. Hundreds performed the sunset prayers. Veiled women prayed separately.

A senior Brotherhood leader, Essam el-Erian, told The Associated Press he was heading to Tahrir Square to meet with other opposition leaders. El-Erian told an Egyptian TV station that the Brotherhood is ready to contact the army for a dialogue, calling the military "the protector of the nation."

Clinton suggested there were U.S. concerns over the possibility of the Brotherhood seizing direction of the movement. She warned against a takeover resembling the one in Iran, with a "small group that doesn't represent the full diversity of Egyptian society" seizing control and imposing its ideological beliefs.

The military was taking the lead in restoring order after police virtually vanished from the streets Friday without explanation after initially clashing with protesters. The disappearance of the police opened the door for a wave of looting, armed robberies and arson in cities around the country.

The anarchy was further fueled when gangs of armed men attacked at least four jails across Egypt before dawn, freeing hundreds of criminals and Muslim militants. Gangs of young men with guns and large sticks smashed cars and robbed people in Cairo.

The official death toll from the crisis stood at 97, with thousands injured, but reports from witnesses across the country indicated the actual toll was far higher.

The military, which enjoys far greater support among the public than the police, fanned out in tanks and armored vehicles around Cairo. At Tahrir Square, they appeared to cooperate with protesters in keeping order, and there were many scenes of affection between soldiers and demonstrators, who allowed troops to use their mobile phones to call home or offered them cigarettes.

"I am glad they are continuing to protest. God willing, he (Mubarak) will go," said one air force captain in uniform who drove by the edge of the square.

One banner held by protesters summed up the military's dilemma: "The army must chose between Egypt and Mubarak."

Minutes before the start of the curfew, at least two jets roared over the Nile, making several passes over the square, dropping lower every time and setting off alarms in parked cars. Some protesters clapped and waved to them while others jeered.

Police began reasserting their presence, moving back into some Cairo neighborhoods. In some spots, they were jeered by residents.

Interior Minister Habib al-Adly said he was ordering security forces to return to the streets in Cairo and elsewhere to work in tandem with army troops to restore order.