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BEIJING, April 27 (Xinhua) -- Air quality in Beijing continued to improve last year as the municipality intensified efforts to prevent and control air pollution, according to a communique released by the Beijing Municipal Ecology and Environment Bureau Monday.

The concentrations of major air pollutants fell remarkably in 2019, said Liu Wei, an official with the bureau.

The average concentration of PM2.5 hit a record low of 42 micrograms per cubic meter, while those of sulfur dioxide, nitrogen dioxide and PM10 were 4, 37 and 68 micrograms per cubic meter, respectively, according to the communique.

In 2019, the number of good air quality days in Beijing totaled 240, or 65.8 percent of the total, 64 more than in 2013, the year a national action plan was issued by the State Council to fight air pollution. Throughout the year, the capital only saw four days of heavy air pollution, 54 days fewer than in 2013.

Beijing actively advanced international exchanges and cooperation and shared green development experience on multiple platforms last year. A UN Environment report launched last March hailed the improvement of air quality in the metropolis, said Liu.