CAIRO - The popular uprising in Egypt triumphed Friday as President Hosni Mubarak surrendered to the will of a leaderless revolution and stepped down after 30 years of autocratic rule over the Arab world's most populous nation.

Mubarak became the second Arab leader in a month to succumb to his people's powerful thirst for freedom. His resignation sparked joyful pandemonium in Cairo and across the country, but the next steps for Egypt were unclear as the armed forces took control and gave little hint of how they intend to govern.

For the moment, however, Egyptians were suffused with a sense that they had made world history, on par with chapters such as the fall of the Berlin Wall and the collapse of communism in Eastern Europe. In a region long devoid of democracy and stifled by repression, Egyptians celebrated with fireworks, a cacophony of horns and a sea of red-white-and-black national flags.

"I feel Egyptian, like I am a new person," said Mustafa Sayed, 52, among tens of thousands of protesters who marched to Mubarak's presidential palace to demand that he leave. "I feel as though my handcuffed wrists and my sealed lips are now free."

Mubarak's abrupt abdication came just 19 hours after the 82-year-old leader had appeared on national television to declare defiantly that, despite the swelling protests against his rule, he had no plans to quit. He left it to his handpicked vice president, Omar Suleiman, to announce his resignation; Mubarak and his wife, Suzanne, then left Cairo, apparently bound for internal exile in the Red Sea resort of Sharm el-Sheikh.

While Egypt's new military chiefs pledged to allow "free and honest" elections, it remained unclear how and whether power might be ceded to civilians, after six decades in which the army has been the country's dominant force.

It was also unclear whether demonstrators' success in winning Mubarak's removal might be followed by a quest for retribution against the former president, his wealthy family or members of his notoriously brutal security services. A group of Egyptian lawyers said they would submit a complaint to the country's attorney general seeking the prosecution of the Mubarak family on corruption charges.

But for at least one day, Egyptians were able to celebrate, backed by international statements of support. "Egypt will never be the same," President Obama said at the White House. " . . . And I know that a democratic Egypt can advance its role of responsible leadership not only in the region, but around the world."

In Tahrir Square, the plaza in central Cairo where the protests began Jan. 25, hundreds of thousands of Egyptians jumped up and down, pumped their fists, waved their flags, hugged and cried. If the people were nervous about their nation's uncertain future, they submerged their anxieties for the moment.

"I feel free," shouted Nihal Shafiq, a 30-year-old film director. "This is a great moment and it hit us by surprise. It is a new beginning for Egypt after 30 years of suffering."

The uprising came soon after the ouster of Zine el-Abidine Ben Ali from Tunisia. Ben Ali, 74, fled the North African country Jan. 14, after four weeks of steadily escalating riots protesting his 23 years in power.

Angered by Mubarak's refusal to resign Thursday night, Egyptians responded early Friday with their biggest demonstrations yet. Ignoring fears that Mubarak might order a brutal crackdown, people of all ages and classes calmly gathered in central squares across the country and in unison demanded a change.