New Delhi, Nov 10 (ANI): Thick layer of smog engulfed the national capital leading to reduced visibility in various areas. Air quality continues to deteriorate in Delhi. According to the Central Pollution Control Board, air quality index is under the ‘severe’ category. Dense smog led to extremely low visibility at the Signature Bridge. The visibility has reduced during morning hours due to fog along with smoke and pollutants. The India Meteorological Department had predicted that air quality is likely to improve on November 12-13 due to easterly winds. In order to put some control on the increasing pollution, state government had banned fire crackers ahead of Diwali.