Hou Zhenrun, owner of an illegal coal mine in Shanxi Province, handed himself over to the police late on Friday night, Gu Shengming, a spokesman with Datong city government told Xinhua.

Hou allegedly gathered eight people to carry out the assault on Lan Chengzhang, and his colleague Chang Hanwen, two employees of the China Trade News, when the two men attempted to investigate Hou's illegal mine in Hunyuan County on January 10.

Lan died of a brain haemorrhage the next morning in hospital. Chang suffered a broken right arm and minor injuries in the attack.

However, the head of the newspaper's Shanxi office said the two, who were employed to collect clues for the paper, were not authorized to conduct reporting missions and their investigation on the coal mine was only "personal behavior".

Lan had an employee's card issued by the Beijing-based newspaper, according to the head of the paper's Shanxi office.

However, only a press card issued by the State Press and Publication Administration can serve as a valid certificate of a journalist's identity.

According to the police, Lan told Chang en route to the coal mine that the mine owner could "at least give us 1,000 yuan (128 U.S dollars) once we show him our identity."

Lan found a doorman of the mine Zhang Gengen and told him they wanted to talk with the mine boss about the mine's operation as they had received reports the mine was run illegally.

Zhang gave the telephone number of Hou who was then in Dadong City. Hou asked Lan on the phone to go to Datong to talk but Zhang insisted on waiting for Hou at the mine.

At 4 p.m., Hou took eight people to the mine and asked them to assault on Lan and Chang.

Hou and the eight fled the scene after the beating.

Police are also questioning three people out of the group of eight suspected of carrying out the beatings. The men are Zheng Wenping and Ma Li, both unemployed from Nanjiao District of Datong City, and Zheng Hongrui, a native of Hunyuan County.