BEIJING — Chinese authorities on Dec 16 launched a nationwide campaign to crack down on illegal mining.

The high demand for coal has shored up prices, prompting the resurgence of illegal coal mining, according to the Office of the Work Safety Committee of the State Council and the Ministry of Emergency Management.

Coal-producing provinces should comprehensively and thoroughly investigate illegal activities, including unauthorized mining and excessive production beyond the approved capacity, said the authorities.

Those involved in unauthorized mining should be investigated for criminal responsibility in accordance with law, the authorities said.

On Dec 15, more than 20 people were trapped after a coal mine was flooded in the city of Xiaoyi, North China's Shanxi province, as a result of illegal mining.