The Chinese authorities have cracked down on a small pro-democracy rally apparently modelled on the protests sweeping the Arab world.

Police detained activists, disconnected mobile phone text messaging services and censored internet postings after an anonymous online campaign to stage protests in Beijing, Shanghai and 11 other major cities.

In Shanghai, protesters were seen being violently dragged away by plain-clothed police officers, and some were detained at a local police station.

One protester described the Chinese government as "a tyranny that suppresses the citizens."

On Sunday, police took at least three people away in Beijing, one of whom tried to lay down white jasmine flowers, while hundreds of people milled about the protest gathering spot outside a McDonald's on the capital's busiest shopping street.

Many activists said they didn't know who was behind the campaign and weren't sure what to make of the call to protest, which first circulated on Saturday on the US-based Chinese-language news website Boxun.com.

The unsigned notice called for a "Jasmine revolution" - the name given to the Tunisian protest movement - and urged people "to take responsibility for the future."

Participants were urged to shout, "We want food, we want work, we want housing, we want fairness" - a slogan that highlights common complaints among Chinese.

The call is likely to fuel anxiety among China's authoritarian government, which is ever alert for domestic discontent and has appeared unnerved by recent protests in Egypt, Tunisia, Bahrain, Yemen, Algeria and Libya.

It has limited media reports about them, stressing the instability caused by the protests, and restricted internet searches to keep Chinese uninformed about Middle Easterners' grievances against their autocratic rulers.