A strong cold front has swept across northern China and helped disperse the smog that had covered a vast part of the country.

The cold air has brought rain and snow in some parts of the northern and northeastern regions. Strong winds have also caused the temperature to drop up to 14 degrees Celsius. Smog in the cities of Beijing and Tianjin, and Hebei Province is being dispersed after covering northern and central China for almost a week.

The National Meteorological Center has issued 12 smog alerts since February 20th, including 9 yellow and 3 orange alerts.China's meteorological alerts are labelled blue, yellow, orange and red in order of ascending severity.