SHANGHAI – China's environment ministry reprimanded provincial officials in Shandong, the country's biggest aluminium producing province, for failing to comply with policies to cut coal consumption and curb the growth of highly polluting aluminium output.

Shandong has been a key part of China's efforts to curb pollution in the industrial north, but it has struggled to find cleaner forms of growth. Seven of the province's cities were set targets to cut smog over the winter, but only one - Jining - managed to do so.

In a review of the compliance record of eight regions published late on Monday, China's Ministry of Ecology and Environment said Shandong officials not only failed to meet guidelines on industrial overcapacity, but also deceived central government inspectors and tried to cover up illegal behaviour.

Shandong was ordered to cap total aluminium production capacity at 4 million tonnes in 2017, but the province's "choices" and policy "adaptations" enabled the industry to expand out of control, with total capacity soaring to as much as 12.6 million tonnes, the ministry said in a statement.

It accused the cities of Binzhou and Liaocheng in particular of allowing and covering up illegal construction in the industry. The cities are home to China's two biggest private aluminium producers, China Hongqiao Group and Xinfa Group.

Aluminium smelting requires large amounts of electricity that plants tend to produce from coal-fired power plants on site that add to air pollution.

Shandong's provincial government said on Monday that 163 officials have now been held to account for a range of violations uncovered by central government inspectors.

As well as failing to control the aluminium sector, they also did not properly supervise efforts to cut coal use, allowed land in protected nature reserves to be misused, and enabled "disorderly development" in the chemical sector.

The Shandong environmental bureau said last week it would carry out a one-month pollution "rectification" campaign in the province, running until May 17. It said it would send eight inspection teams to 18 cities, including the major aluminium smelting centres of Binzhou and Liaocheng.