After the heavy air pollution this winter, the summer in Beijing doesn't look like as if it will get any better, remaining at severely unhealthy levels on May 6, according to the Beijing Municipal Environmental Monitoring Center.

The center suggested that everyone reduce outdoor activities and asked the elderly, children and sick people to take protection measures before going out.

As of 4 pm, the air at all 35 monitoring spots in the capital was severely polluted, with the PM2.5 level reaching 401 in downtown Xizhimen.

The center issued a yellow alert for smog on Monday morning, saying that the smog on Monday will last until night with visibility less than 3,000 meters.