ULAN BATOR, Nov. 25 (Xinhua) -- Mongolia's capital Ulan Bator recorded a year-on-year decrease in the density of hazardous fine particulate matter PM2.5 in the first two weeks of November, the city's Air Pollution Reduction Department said Monday.

According to the department, the average concentration of PM2.5 in the air of Ulan Bator dropped to around 120 micrograms per cubic meter during the period, down 55 percent from a year earlier.

In the meanwhile, the average density of PM10 stood at 170 micrograms per cubic meter, down 38 percent year on year, it said in a statement.

The department attributed the reduced air pollution to a government ban beginning May 15 on the domestic use of raw coal fuel.

Since then, households in the city have been supplied with processed fuel instead.

In addition, the city stepped up efforts to check the use of the raw coal fuel, with 7 tons of raw coal seized since October, according to the statement.