Beijing:
The smog blanketing the Chinese capital forced authorities at Beijing's international airport to cancel a score of flights on Wednesday.
Flights bound for Russia, Singapore and the United States were among those grounded due to poor visibility, terminal managers said on the airport's web site.
Monitors installed at the US Embassy in Beijing registered an air-quality reading of 430 at 1 p.m. on Wednesday. A reading of 500 indicates maximum danger.
The monitors also detected a concentration of tiny particulates - dangerous because they can enter the lungs or bloodstream - of 395 micrograms per cubic meter of air, 15 times the level deemed acceptable by the World Health Organization.
Visibility in Beijing was less than 100 meters on Wednesday, according to the weather service.
The capital suffered its worst air quality on record during the period of January 10-16.
Beijing's acting mayor, Wang Anshun, announced on Tuesday a series of pollution-reduction measures, including a programme to get older vehicles off the roads.
Scientists say, however, that much of the pollution affecting the capital is generated by heavy industry in neighbouring provinces.