Thousands of people in southern China held a second day of protests on Tuesday after police encircled their village following the death of a local community leader in detention, witnesses said.

Residents of Wukan in the southern province of Guangdong accuse the police of beating Xue Junbo to death -- a claim denied by the authorities, who say he died of natural causes while in their custody.

He was detained last week along with four other men over riots that took place earlier this year to protest against government land grabs in the village.

"This afternoon, over 6,000 villagers have gathered as they did yesterday, shouting slogans like 'save Wukan' and 'return our farmland'," one man who refused to identify himself told AFP.

"The government is discussing compensation with Xue's family, but they have refused to meet villagers to discuss the land issue," the man said.

The Lufeng government, which oversees Wukan, said that police, riot police and firemen with water cannon had been deployed to the village to "ensure stability".

Villagers contacted by AFP also accused the government of beating the four other village representatives who were arrested with Xue on Friday, but denied reports that a second man was beaten to death.

They said the arrests were linked to the September riots in which hundreds of demonstrators attacked a police station and ransacked vehicles.

Residents have accused authorities of forcibly grabbing their land and not compensating them, but the government has insisted the process was lawful.

Land grabs have become a hugely contentious issue in China, where authorities are accused of colluding with developers in lucrative real estate deals that have become an important source of government revenue.

On Monday, villagers complained that police had blockaded the village for days, cutting off access to the Internet and making it difficult to transport in food and supplies.

On Tuesday, authorities blocked Internet searches on the name of the village in an apparent effort to stop news of the unrest from spreading.

The government has said Xue suffered a "sudden cardiac death".