Chinese authorities have issued air pollution warnings for 10 additional cities, following two "red alerts" announced by Beijing this month that covered the capital and several other major cities in the country's east.

A red alert is the highest of a four-level warning system aimed at communicating to the public the amount of hazardous particles in the air. The alert is triggered when the government believes air quality is projected to be unhealthy for at least three consecutive days. Under the alert, government agencies direct people to stay indoors, advise schools to cancel classes, and restrict use of vehicles.

The latest alert covers the cities of Tianjin, Puyang, Xinxiang, Dezhou, Handan, Xintai, Langfang, Hengshui, Xinji, and Anyang.

Cyclists in Zhengzhou wear masks, while riding along a road in heavy smog. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)

The warnings come following a landmark UN climate agreement was reached earlier this month that set a course for nations to transition away from fossil fuels within just a few decades.

A tour boat sails through heavy smog in Suzhou, China. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)

State news agency Xinhua blamed the smog on northern China's reliance on coal for its energy needs.

"From a long-term perspective, the improvement in air quality cannot just rely on temporary production suspensions or limitations for certain companies," it said. "Fundamentally it needs to come from an adjustment in industry and energy structure, as cutting emissions from the source is the permanent solution."

A man does morning exercises in heavy smog in Dezhou,China. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)

After decades of unbridled economic growth, China's leadership has vowed to crack down on environmental degradation, including the air pollution that blankets many major cities.

Air pollution is responsible for killing as many as 1.6 million Chinese people per year, according to a study by Berkeley Earth — a rate of roughly 4,400 people a day. China Daily, a state-run newspaper, recently reported that lung cancer diagnoses in the country could climb to more than 800,000 a year by 2020.

A train travels along a bridge in heavy smog in Beijing, China. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)

Environmental Protection Minister Chen Jining vowed on Sunday to punish agencies and officials for any failure to quickly implement a pollution emergency response plan, the state-owned Global Times reported. His ministry also said that it is sending teams of inspectors to various areas of the country to make sure that they are complying with emergency measures and environmental regulations.

A man does morning exercises at a park in heavy smog in Wenxian, China. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)

Chinese researchers have said that the dangerous levels of smog are becoming a point of unrest for the country's 1.3 billion citizens. City residents have previously criticized authorities for being too slow to issue red alerts for heavy smog.

A woman poses for photos in heavy smog in Suzhou, China. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)

A salesman dressed as Santa Claus wears a mask in heavy smog in Jinan, China. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)

A dog wearing a mask and his owner walk along a road in heavy smog in Hangzhou, China. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)

Heavy smog blankets Donggang CBD in Dalian, which is located in northeast China's Liaoning Province. (Photo via Xinhua/Wang Hua via Getty Images)

Vehicles run in heavy smog in Shijiazhuang, Hebei Province of China. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)