Media playback is unsupported on your device Media caption Security forces have sealed off the Kazakh oil town of Zhanaozen

A state of emergency has been declared in the western Kazakh town of Zhanaozen a day after clashes between strikers and police left at least 11 dead.

Strikes and protests are banned, a night-time curfew introduced and movement restricted for 20 days.

Clashes began on Friday as police tried to clear the town square, occupied by oil workers for more than six months in a dispute over better pay.

It is the worst violence in the Central Asian nation's recent history.

The town of 90,000 is now said to be calm.

Eyewitnesses said police fired on unarmed protesters, but the authorities say they were forced to defend themselves.

Eighty-six people were injured - according to official figures - and some had to be taken to hospital in Aktau, some 150km (90miles) away, due to a shortage of beds in Zhanaozen.

"Roads into Zhanaozen have been blocked, military forces brought into the city, and helicopters are circling above. There is still no mobile phone coverage, and internet access in the region has been disconnected", says BBC Russian local reporter Dinmukhammed Kalikulov.

'Bandit elements'

Dozens of buildings including government and oil company offices were attacked, cars were set on fire and shops and banks looted, President Nursultan Nazarbayev told a security council meeting on Saturday.

The government would need the 20-day state of emergency to restore order, he said.

Mr Nazarbayev defended the police, saying they had acted within the law. He expressed condolences to the families of victims, promising help from the government.

But he also warned that the clashes should not be confused with an industrial dispute, and called them the work of "bandit elements".

He promised to send a commission from the state oil company to Zhanaozen to resolve the dispute.

While government officials said 11 people died as a result of Friday's violence, opposition media sources put the figure much higher with some reports talking of dozens of deaths.

So far, 70 people suspected of taking part in the disturbances have been detained, the prosecutor-general's office told a news conference.

The clashes came as Kazakhstan marked the 20th anniversary of independence from the Soviet Union, with celebrations throughout the country.

Correspondents say the unrest will have been a shock to President Nazarbayev, who came to power just before independence and has kept a tight rein on public protest.