Beijing has continued to witness heavy air pollution, which started last week before the Chinese New Year.

Data registered at 10 a.m. on Saturday showed the city's air quality index had reached the level of heavy pollution, with the PM 2.5 concentration in the city's urban areas hitting 239 micrograms per cubic meter, reports Xinhua news agency.

Local authorities had issued a yellow alert for heavy air pollution on February 11, the first day of China's Spring Festival holiday.

China has a four-tier color-coded warning system for air pollution, with red the most serious, followed by orange, yellow and blue.

Conditions for atmospheric diffusion during the first half of this year's Spring Festival holiday are the worst in recent years, making it hard for pollutants, including those from the burning of fireworks, to dissipate, the municipal ecology and environment bureau noted.

The conditions for atmospheric diffusion are expected to improve on February 15, according to a forecast by China National Environmental Monitoring Center.

(IANS)