J. Adam Ereli, a State Department spokesman, denied Russian assertions that the revolt was organized by the United States. The uprising was due to "a negative public reaction when the accepted processes for political expression and political change are tampered with and when the rule of law is not followed," he said.
The opposition freed Felix Kulov, a former interior minister, from jail in the uprising, and analysts said he could become a significant figure as the country moves toward new presidential and parliamentary elections.
Protesters pursue riot police as they storm government headquarters in Bishkek, Kyrgyzstan. Several people were injured in the demonstrations.
(Gleb Shchelkunov -- AP)
Video: Protesters stormed the presidential compound in Kyrgyzstan on Thursday, seizing control of the seat of state power after clashing with riot police.
A Look at Kyrgyzstan
Kulov was arrested after saying he would run against Akayev in 2000 and sentenced to 10 years on embezzlement and abuse of power charges, which his supporters have said were politically motivated.
After his release, he declared on national television that this was a "revolution made by the people. . . . Tomorrow will come, and we must decide how to live tomorrow."
The day began with opposition protesters assembling on the outskirts of Bishkek. Interior Minister Keneshbek Dushebayev, who was appointed only Wednesday and was considered a pro-Akayev hard-liner, addressed the crowd and seemed to pull back from earlier warnings that his forces could use "special means and firearms" against the opposition. He urged protesters to obey the law but told them police would not use force against anyone who was unarmed.
The crowd marched on the huge stone government compound, gathering people along the way. The protesters' first attempt to break through police lines failed, according to reports from the scene. Several people were injured in clashes between protesters and the president's supporters.
Security forces stood down, however, when demonstrators made a second attempt to get into the building, suggesting that entry had been negotiated in an attempt to avoid more serious violence.
"It didn't take long," said Shakirat Toktosunova of the Eurasia Foundation, which funds democratic projects. "A group of people from different regions came to Bishkek and all went to the center. It didn't take more than a couple of hours for them to take over the president's office."
Ulan Shambetov, an opposition figure, spoke to reporters as he sat at a desk in Akayev's wood-paneled office. "It's not the opposition that has seized power, it's the people who have taken power. The people," he said. "They have been fighting for so long against corruption, against that family," a reference to Akayev and his relatives.
Protesters tossed computers and paper from the windows of the government building, smashed furniture and crushed portraits of Akayev. Outside, several government Mercedes were set alight, according to local reports. "One of the large supermarkets was broken into, the windows shattered," Toktosunova said in a telephone interview from the capital.
Events moved rapidly after the building was seized. The opposition took control of a pro-government television station and organized the release of Kulov, the former interior minister, who then addressed the nation on television. Prime Minister Nikolay Tanayev tendered his resignation. Bakiyev, the opposition leader, said senior officials in the security, interior and defense ministries had begun to work with the new authorities.
Opposition leaders sought to rein in young supporters. "We will establish order. We will not allow looting. We will hold our own elections to start our rule," Bakiyev said.
The revolt began in earnest Sunday and Monday when the opposition took control of Osh, the country's second city and largest city in the south, and nearby Jalal-Abad. There is a strong north-south regional divide in the country, exacerbated by the south's relative poverty.
Reaction in Russia, which also has troops in Kyrgyzstan, was muted. The Foreign Ministry said little more than that the opposition should act within the law.
After fallout from its role in Ukraine, where the Kremlin openly backed the losing candidate and dismissed the popular protests, the Russian government appears more reconciled to change. In the run-up to the elections in Kyrgyzstan, it had pointedly met with leading opposition figures when they visited Moscow.
Finn reported from the Czech Republic. Staff writer Robin Wright in Washington contributed to this report.