Opposition protesters, using clubs and petrol bombs, seized Kyrgyzstan's second city, Osh, Monday as increasingly violent unrest swept the south of the country aimed at forcing President Askar Akayev to step down.

Central Asian Kyrgyzstan has become the latest former Soviet republic - after Ukraine and Georgia - to be rocked by anti-government protests in the wake of elections judged as flawed by international observers.

Akayev's spokesman said the president was ready to hold talks with the opposition.

``The most important thing right now is to let people calm down, assess what has happened and then start negotiations with them about their demands,'' said Abdil Segizbayev on Kyrgyz television, though few in riot-hit towns appeared to be listening.

Police and officials in Osh fled Monday when a crowd of about 1,000 young men armed with sticks and petrol bombs stormed the regional administrative building, setting fire to a portrait of Akayev and chanting ``Akayev Go!''

Activists stormed the administrative building Friday but were ousted by security forces Saturday before retaking it Monday. The protesters then grew in number to about 2,000 and overran the regional police and security stations in the city, about 300 kilometers south of the capital, Bishkek.

``This is a new day in our history,'' said Omurbek Tekebayev, an opposition activist. He said the opposition would create alternative government bodies throughout the country.

Another opposition member, Anvar Artykov, told the crowd that ``power in Osh has been taken over by people. I congratulate you on our victory and urge you to maintain order.''

Opposition activists had taken control of the nearby town of Jalal-Abad overnight after violent clashes with police. Four officers were reportedly beaten to death as about 15,000 demonstrators burnt down much of the police headquarters, freed 70 detained protesters and occupied the governor's office.

The central police station was a smoldering ruin Monday and there were no police or officials to be seen. The airport was closed and piles of rocks had been placed on the runway to stop the government flying in troops. The opposition was also occupying government buildings in four other cities and towns, said Interior Ministry spokesman Nurdin Jangarayev.

And hundreds were rallying in at least two other towns in the nation of five million people. Protesters in the southern town of Toktogul held captive for a third day a district governor and a chief district prosecutor - both accused of colluding with Akayev's government.

``Unfortunately, the situation is spinning out of control,'' said Kurmanbek Bakiyev, one of the leaders of the loose opposition coalition, in Bishkek. It ``cannot be any more explosive than it is at the moment.

``Ordinary people living in the south start saying, `If the authorities don't care about us, let's secede.'''

The north, including the capital, remained calm Monday. Akayev, 60, has warned any attempt to copy Ukraine's ``Orange Revolution'' could drag the mostly Muslim country into civil war.

The south has a large ethnic Uzbek population where many resent what they see as the north's political dominance and greater prosperity.

Analysts said that despite the ethnic divide it was more economic concerns that were driving the unrest. But they added there was a danger in the current environment that ethnic tensions which led to bloodshed in the 1980s and 1990s could resurface.

Akayev, who comes from the north, cancelled a public address in Bishkek to mark the Muslim spring holiday of Novruz.

His press secretary said the president had yet to determine when, and in what format, the talks would take place.

Neither was it clear who, if anyone, was in control of the protests.

Seghizbayev said security forces would not take action against the protesters, but peace talks would only be possible after order was restored.

``Neither authorities nor opposition leaders can control the crowd right now,'' he said.

If an opposition leader emerges ``who can control the protesters,'' he added, ``the government will be ready to talk to him.''

REUTERS, ASSOCIATED PRESS