Environmental officials in China warned a heavy blanket of smog will hang over Beijing and surrounding cities through the weekend, UPI reported. The capital city's environment monitoring center told China's official Xinhua news agency Saturday not to expect the thick smog to clear out before Monday. Much of eastern and central China has been putting up with heavily polluted air that has reduced visibility enough to cancel airline flights and close roads in some areas. The level of particulates in the air has soared to the point that children and the elderly were being advised to stay indoors until further notice. The BBC said the air quality had surpassed the danger levels set by the World Health Organization. The report said there was so much exhaust and coal dust in the air in Beijing it could be tasted.