BEIJING—A Chinese court handed environmental groups their first victory under a new law making it easier to sue polluters, which green groups hope can be a powerful tool for tackling the country’s pernicious pollution problems.

The court in China’s southern Fujian province ordered four mine operators to pay 1.27 million yuan (about $200,000) in cleanup costs, as well as the legal costs of Friends of Nature and Fujian Green Home, two environmental groups that brought the suits. Friends of Nature estimated those at 165,000 yuan.

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