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Cairo, Egypt (CNN) -- Demonstrations that began with quiet determination on the internet more than three weeks ago erupted into riotous jubilation Friday evening, moments after it was announced that Egyptian President Hosni Mubarak was stepping aside.
Protesters swarmed army tanks that had been deployed to keep order, banged drums, blew whistles and frantically waved Egyptian flags in celebration. They danced in circles and chanted. Processions of cars made their way down city streets, drivers honking horns and waving flags.
Fireworks erupted outside the presidential palace in Cairo and in the streets of Alexandria. Some men and women dropped to their knees and began to pray.
"I did not believe it at first," Egyptian-American Sarah el-Helewsaid. "I feel complete joy."
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"Freedom!" crowds chanted outside the white carved walls of the presidential palace.
"God is great!" they shouted in Tahrir Square.
On the front lines of the movement, protester and actor Khalid Abdallah, best known for his role in "The Kite Runner," expressed complete shock at Mubarak's decision to step down, but said Egyptians now feel like "destiny is in their hands," and he praised supporters of their struggle.
"Thank you to everyone who has stood in solidarity with us," Abdallah told CNN's Wolf Blitzer. He said Egyptians are grateful for those who "told our true story."
Abdallah recounted seeing and hearing the voices of children. "Hold your head high," Abdallah said they chanted, "you're an Egyptian."
Fears that the Muslim Brotherhood, an Islamic umbrella group, could hijack Egypt's pro-democracy movement have made headlines during the 18 days of protests in the country, but the group has stated more than once that they are not seeking power. On Friday, they celebrated the news of Mubarak's departure with the rest of the Egyptians.
"We are opening a new bridge now on history," Muslim Brotherhood spokesman Essam El Erian told CNN. "This is [a] critical moment." Erian said of the pro-democracy revolution that he said he believes will shape the future of Egypt.
In Alexandria, Fatima Puskar, an American living with her Egyptian husband, Emad, said she was watching Egyptian state TV when news of Mubarak's resignation was announced.
"We could hear people, even before the end of the statement I heard people outside of the window shouting and honking their horns," she said.
Omar Sultan of Cairo said he felt like he played a role in forcing Mubarak to resign by taking part in demonstrations.
"Everyone is very happy. No one imagined this day would come," he said. "I've never been prouder to be an Egyptian."
Two of the main bridges connecting east and west Cairo were like parking lots as people got out and began hugging and dancing.
"Life is great now. I think I will have a much better future now. It is a different era," a 17-year-old girl named Fatima told CNN.
The news of Mubarak's resignation, and the revolution that led to the announcement, has also sparked a renewed spirit and proud voice for Egyptians.
"I stopped writing -- as a journalist -- because I felt there was nothing to write about," said Salah Marakby, a 76-year-old retiree. "But I feel now that the pyramid of corruption has fallen. I want to go back to writing now!"
One of the movement's key activists, Wael Ghonim, credited ordinary Egyptians for persisting through historic and sometimes violent protests that led to the first ouster of an Egyptian leader since 1952.
"Congratulations Egypt the criminal has left the palace," said Ghonim, who was jailed for a week and a half by the Mubarak regime and whose emotional commentary after his release helped galvanize protesters.
Addressing Mubarak and his allies, Ghonim said the country should hold them accountable for their actions, including the deaths of protesters killed during what had been peaceful demonstrations.
"I just want to say to Hosni Mubarak and to Omar Suleiman and to all those people who thought that being in power means you can oppress people, you know, hard-luck guys, you know, at the end of the day, we have a choice and we've made our choice," he said.
"They convinced us for 30 years that Egypt had died, that there was no more Egypt," he said in an interview with CNN, referring to the nearly 30 years of autocratic rule under Mubarak. "We were all looking for Egypt and thank God we found her today."
Ghonim, who helped set up the initial Facebook page calling for protests, said it was time to celebrate, and said he has confidence that Egypt will not fall into dictatorship again.
"Today, I am telling you Egypt is going to be a democratic state," said Ghonim, who is on leave of absence from his job at Google.
Mohamed ElBaradei, a leading opposition figure, showed his support for Mubarak's decision to step down through Twitter. "Egypt Today is a free and proud nation. God Bless," was posted by ElBaradei Friday night on the social media website.
Amre Moussa, secretary general of Arab League, said he is optimistic that the country is on the right path.
"We have achieved what the people wanted," he said. "Now we must build a new Egypt."
The future many Egyptians had dared to imagine seems much brighter now.
"No matter how hard things are," Abdallah said, "you can get through and you can keep dreaming."
"Today is our time," a 46-year old woman told CNN. "We have learned that it is not too difficult to change. Sadly, some people died on the way."
Egypt's ambassador to the United States spoke with CNN Friday about the what it will take to form a new democratic government and whether future elections will be fair and open.
"Certainly the voice of the people has been heard loud and clear," Sameh Shoukry said. "It will be the ballot box and the voice of the Egyptian people that will determine the direction of any future governments."
CNN's Amir Ahmed contributed to this report.
