Start of heating season adds to problem; no relief until Friday

Beijing shut down 13 expressways on Wednesday due to heavy fog in Beijing and surrounding regions, according to transportation authorities.

At 1 pm, the air quality index in Beijing was 301, a level-six air pollution.

Air pollution is worsening in the Beijing-Tianjin-Hebei province region and nearby areas and is expected to linger until Friday due to unfavorable meteorological conditions for dispersal, authorities said.

Anyang, Henan province - listed as one of the 28 major cities in the region for coordinated action on air pollution control - was the first to see its hourly density of PM 2.5, a major air pollutant, reach heavy pollution level early on Monday. The heavy pollution has gradually been extending to the north, the China National Environmental Monitoring Center said in a statement on Tuesday.

Pollutants started to accumulate on Monday in the region and in the Fenhe and Weihe river plains, primarily in Shanxi and Shaanxi provinces, as meteorological conditions turned unfavorable.