After continuous confrontation between villagers and local officials for almost four months, the land grab in the fishing village of Wukan, in Guandong province, China, has now led to the death of one of the elected village leaders in police custody, and further escalated into a violent "mass incident" with tens of thousands of farmers protesting against local officials.

The Wukan case is just one of many mass incidents China has experienced in recent years. In fact, the number keeps rising every year; journalists often cite a figure of 87,000 for 2005, estimates by the China Academy of Social Sciences give a figure of "over 90,000" mass incidents in 2006, and further unspecified increases in 2007 and 2008.

In China, a mass incident is defined as "any kind of planned or impromptu gathering that forms because of internal contradictions", including mass public speeches, physical conflicts, airing of grievances, or other forms of group behaviour that may disrupt social stability. Among China's mass incidents, more than 60% have been related to land disputes when local governments in China worked closely with manufacturers and real-estate developers to grab land from farmers at low prices.

In a drive to industrialise and urbanise, thousands of industrial parks and many thousands of real estate development projects have been, or are being, built at the costs of dispossessed farmers. The land requisition system deprives three to four million farmers of their land every year, and around 40-50 million are now dispossessed.

The Wukan case says a lot about the serious tension between state and society in the fast urbanising China. It is difficult to play the land requisition game fairly under the current system, since farmers are neither allowed to negotiate directly on the compensation package, nor are they allowed to develop their own land for non-agricultural purposes. They have to sell their land to local government first, which defines the price then leases the land to industrial and commercial/residential users for a profit. As land prices keep rising in China, it is not surprising that farmers with rising expectations are becoming increasingly unhappy. As a result, mass incidents, sometimes as violent as in Wukan, are inevitable.

Local authorities in China, in their pursuit of revenue via aggressive urbanisation and industrialisation, are also undermining the country's grassroots democracy. It was usually local officials who would carry out difficult negotiations with village collectives, or who were in charge of coercing defiant farmers to accept government terms. Having village cadres who shared their interests would not only lower the selling price but also determine whether or not the transaction could take place at all. Therefore, township and county officials in localities that experienced greater land requisition had a stronger incentive to manipulate village democracies to make sure that more co-operative cadres were elected.

One township party secretary I interviewed in Fujian province said: "If election rules are followed strictly, [we] will lose control of the rural society. Village cadres will be afraid of villagers, not the township government. They can put off assignments from the township government and compromise the tasks during implementation. Therefore … local officials are willing to introduce rules that subvert the true meaning of village democracy. This is also the case in Wukan in which farmers are protesting not only against local governments, but also against villager cadres who worked with the authorities in abusive land requisition.

As China is urbanising fast, land requisition takes place in more Chinese villages, in particular those closest to the cities. Farmers with rising expectations on the one hand, and local officials with financial stakes in keeping the compensation low on the other, are bound to lead to increasingly violent mass incidents. Local governments in China needs to spend more not only on compensating farmers, but also on maintaining social stability. Wukan should be a signal for China to reform its land requisition system in order to keep local governments away from the financial gains of abusive land taking.