A paper soldier, who lives on the fringes of China’s military and is paid as little as $1,000 a month, was detained and beaten up by soldiers on Saturday, an official said.
The man, identified only as Yang, was on his way to work when he was detained at around 8am on Saturday by soldiers at a military checkpoint in the eastern province of Hubei, the official Xinhua news agency said.
He was charged with being an illegal worker, the news agency reported.
Yang was detained in the area of the border town of Dongguan, according to the official.
The Chinese Communist Party does not recognise the paper soldiers as an independent force, which has been accused of abuses and has been subject to a crackdown in recent years.
The official told reporters on Saturday that the man was released from hospital and is being treated for injuries sustained during the incident.
He is not being named as he is under investigation.
The violence came amid rising tensions between China and Vietnam, which accuses Beijing of supporting the rebels and is accused of a series of human rights abuses in the South China Sea.
China claims most of the South and South-East Asian waters but many of the rival claimants dispute it.
China has warned that it will not back down, but it has also warned that its actions are not enough.
China says the rebels are China’s “paper soldiers” but the rebels deny it.