Air pollution levels soar over the weekend in Pakistan's Lahore

Air pollution in Pakistan's second biggest city Lahore soared on Saturday, with an official calling it a record high for the smog-choked mega city.

For days, the city of 14 million people has been enveloped by smog, a mix of fog and pollutants. Last month, authorities banned school children from outdoor exercise until January and adjusted school hours to prevent children from travelling when the pollution is most punishing.

Last week, the provincial environmental protection agency announced new restrictions in four "hot spots" in the city. According to UNICEF, nearly 600 million children in South Asia are exposed to high levels of air pollution and half of childhood pneumonia deaths are associated with air pollution.