DELHI, INDIA - JANUARY 27: Unidentified people walk on busy street on January 27, 2011 in Delhi, India. Delhi is the world's second most populous city and the largest city in India.
Delhi, India - November 21, 2017: Vehicles traveling on the road in heavy smog.
Delhi, India - November 21, 2017: Vehicles moving in the road amidst smog.
Delhi, India - November 21, 2017: Auto rickshaw traveling in a busy road.
DELHI, INDIA - 19TH MARCH 2016: A view along roads in Delhi during the day showing buildings, Tuk Tuks, rickshaws, cars and people.
Delhi, India - November 21, 2017: Vehicles moving in the road amidst heavy smog.