Smog that has shrouded the Chinese capital since Sunday might persist for a few days, the Beijing Environmental Protection Bureau said on Monday.

Because of the low-pressure system in the atmosphere, the smog, which came on Sunday and worsened on Monday, is likely to persist until Thursday, as weather patterns will not help disperse it, said Xiang Kaiyue of the bureau's publicity staff.

The downtown area saw a PM2.5 intensity of 258 micrograms per cubic meter around noon, while the particulate level in the southwestern part of the city soared to 288 micrograms per cubic meter, according to the Beijing Environmental Monitoring Center.