WUHAN, Jan. 9 (Xinhua) -- More than 100 people are now under police investigation and four have been detained following the beating to death of a man who attempted to film a conflict between "Chengguan", or urban management personnel, and villagers in central China's Hubei province.

    Wang Faliang, vice mayor of the city of Tianmen, told Xinhua that those under investigation included Qi Zhengjun, Under-Secretary General of Tianmen city government and head of the Tianmen Municipal Administration Bureau.

    It was earlier reported that 24 people were being questioned by police.

    An autopsy has been carried out on the body of the victim Wei Wenhua and is being further examined by experts with the Hubei Provincial Department of Public Security, according to Wang.

    Wei, 41, general manager of a Tianmen construction firm, was beaten to death on Monday afternoon when he was trying to use his cell phone to record a clash between more than 50 workers from the Tianmen Administration Bureau and villagers.

    The fracas happened when residents from Wanba Village were trying to prevent a garbage vehicle from the local bureau's sanitation department from dumping garbage at a site near the village.