Authorities in north China's Shanxi Province have detained 137 people and fined polluting companies more than 125 million yuan (around US$18.2 million) in a 100-day campaign against pollution.

Shanxi's provincial environmental protection bureau launched the campaign after media found state-owned Shanxi Sanwei Group Co. Ltd. had been illegally dumping solid waste on the farmland and discharging waste water into Fenhe River, a major river in the province.

The campaign, lasting from May 5 to Aug. 15, consisted of province-wide inspections on nearly 25,000 industrial enterprises, including 3,000 pollution-intensive companies, according to the provincial environmental protection bureau.

A total of 286 companies have been shut down during the campaign.

The move falls in line with a larger nationwide campaign to fight pollution and environmental degradation. Tackling pollution has been listed as one of "the three tough battles" that the country aims to win in the coming three years.

In mid-September, China's national environmental authority has named and shamed 158 companies that discharged major pollutants at seriously excessive levels in the first quarter of 2018.