Beijing - A riot involving hundreds of villages and police in northern China's Shanxi province was caused by a dispute over compensation for the death of a worker, state media said on Saturday.

Police in Shanxi's Pingyao city said the villagers in Wangjiazhuang were led by relatives of a man who died of a heart attack while working as a gate keeper at a local agricultural firm, the official Xinhua news agency said.

The man's foster son, Duan Qijun, was accused of leading "more than 150 people wielding wooden rods to block both gates of the company" on Friday morning in a bid to win more compensation. the agency said.

The riot lasted for about two hours until police ended it an and detained 77 people for "disrupting social order".

Most of the 77 people detained were migrants from other provinces and were allegedly paid between 100 yuan and 200 yuan (14 dollars to 29 dollars) to join the riot, the agency quoted police as saying.

The police were still looking for Duan, it said.

The Hong Kong-based Information Centre for Human Rights and Democracy on Friday said the was spurred by alleged vote-buying before a village election on Saturday.

The centre said about 50 villagers were injured and around 200 detained.

But Communist Party officials in Pingyao refuted those figures and denied that the riot was connected to alleged vote-buying, the agency said.

Elections in the village started as scheduled on Saturday and the situation in Wanjiazhuang was "peaceful", it said.

The riot is the latest in a string of protests reported by state media in recent weeks. (dpa)