Top Kyrgyzstan officials alleged Friday that the opposition, which has declared a nonstop anti-government rally in the capital, had planned a coup.
Prime Minister Felix Kulov told a government session that an unidentified person had handed over a recording of a conversation between opposition leaders and representatives of an unspecified non-governmental organization discussing a coup in the turbulent ex-Soviet state.
"They talked about seizing the city hall, the Committee for State Security, state television and some buildings in the provinces," Kulov said.
"There is no power in the country that can succeed in a coup," he warned.
Part of the recording was played at the government session, and voices resembling those of opposition leaders Omurbek Tekebayev and Almazbek Atambayev could be heard amid background noise, but the words were not discernible to reporters in the hall. A transcript of the alleged conversation was distributed to lawmakers and reporters.
The opposition rejected the allegations as "a provocation."
Tekebayev threatened to sue Kulov and the chief of the government security agency for "eavesdropping on conversations" in his office.
"There was no coup attempt," he told journalists in the city square.
"By rallying here we are forcing the government to initiate talks on the constitutional reform," said Rosa Otunbayeva, now an opposition activist but once an ally of President Kurmanbek Bakiyev. "There will be no attempts to topple the government by force."
Bakiyev refused to step down in the face of Thursday's protests, which brought some 30,000 people into the streets, but opposition forces vowed to keep up the pressure to force him to resign in a dispute over proposed political reforms that would cut his powers, the AP reports.
Shops and markets closed in fear of a repeat of the dramatic March 2005 protests that drove the former Soviet republic's longtime leader Askar Akayev from power - he fled the country as opposition supporters swarmed his headquarters - and were followed by massive looting in the capital, Bishkek.
Hundreds of police in riot gear and with German shepherd dogs have been deployed around the presidential headquarters.
Bakiyev was appointed after the uprising that forced out his predecessor and elected months later, but political tension has persisted. The former opposition figure's rule has been marred by high-profile slayings, prison riots, economic ills and battles for control of lucrative businesses.
"Kyrgyzstan was the first Central Asian nation to have a revolution, but it has borne bitter fruit," said protester Rabina Askarova, 48, a teacher who recently lost her job. "We need to find those who would care for the people and whom we could trust."
The president's critics are increasingly angry over his foot-dragging on constitutional reforms that would curtail presidential powers and give parliament and the Cabinet broader authority, and have demanded he fire top officials accused of corruption and other abuses.
The crowd of protesters in front of the presidential headquarters on Bishkek's central square reached 30,000 at its peak Thursday. A few hundred remained to spend the night in the approximately 100 tents they set up on the square. About 1,500 protesters were there Friday morning.
Tents in squares have become a powerful symbol for government opponents of ex-Soviet republics since Ukraine's 2004 Orange Revolution, when weeks of massive, round-the-clock street protests helped reverse a fraud-marred election result and bring an opposition leader to power.
Teimir Saviyev, a leader of the For Reforms movement, said protesters would remain on the square until Bakiyev stepped down. But he pledged there would be no repeat of the March 2005 upheaval, when protesters abruptly stormed and seized Akayev's headquarters on the first day of a major demonstration.
Bakiyev said he would submit an amended constitution to Parliament on Monday, and would initiate a national referendum if lawmakers failed to approve it within 10 days. But he gave no details, and it was unclear whether his proposals would soothe the opposition.