BEIJING, March 24 (Xinhua) -- Chinese cities reported more days of good air quality in February as the government intensified efforts to crack down on polluters, official data showed.

Last month, 338 cities monitored by the Ministry of Ecological Environment enjoyed good air quality on 75.9 percent of days, up 4.8 percentage points from the same period last year.

In the Beijing-Tianjin-Hebei region, the share of days with good air quality during the month stood at 63.4 percent, a year-on-year rise of 9.3 percentage points, according to the ministry.

The density of PM2.5, fine particulate matter that causes smog, in Beijing went down 29.6 percent to 50 micrograms per cubic meter during the month.

The city of Haikou in Hainan Province continued to have the cleanest air out of the nation's 74 major cities, while Xingtai in Hebei Province was the worst polluted.

After decades of rapid development that left the country with a thick, gray haze, China declared a war against pollution, with intensified efforts to crack down on polluters and incentives for clean energy use.

To clear up its air, China has been encouraging the use of natural gas instead of coal for winter heating, subsidizing new energy vehicles to curb emissions, and shutting down ineffective factories that produce the most pollution.

Authorities also demonstrated "zero tolerance" for polluters, launching a pollution control campaign targeting about 62,000 irregular enterprises in the Beijing-Tianjin-Hebei region and surrounding cities last year.