BEIJING — China announced on Oct 18 that it will limit its annual mining of rare earth within 140,000 tonnes by 2020 in its latest attempt to overhaul the sector and ensure its sound development.

The government will continue to investigate and apprehend anyone involved in illegal mining, processing or trade in rare earth metals and better manage market access, according to a rare earth development plan for the 2016-2020 period, released by the Ministry of Industry and Information Technology (MIIT).

Rare earth comprises a class of 17 mineral elements which are some of the most sought-after metals due to their vital role in green technologies like wind turbines and car batteries. They are also used for military purposes.

China is the world’s largest rare earth producer and exporter, but the industry is beset by myriad problems, such as illegal mining, smuggling and a lack of competitiveness due to weak research and development. Excessive exploration has also caused environmental damage.

To upgrade the industry, the MIIT plans to improve efficiency across resource management and technological innovation by 2020.

During the 12th Five-Year Plan period (2011-2015), 14 illegal rare earth mines and 28 companies were closed. More than 36,000 tonnes of illegal rare earth products were seized, and 230 million yuan in fines was imposed, according to statistics from the MIIT.