Diwali, derived from the word “Deepavali,” meaning “a row of lights,” is typically celebrated by socializing and exchanging gifts. The dates of the festival are based on the Hindu lunar calendar, typically falling in late October or early November. Shoppers crowded markets to buy flowers, lanterns and candles.

Thick smog blanketed India’s capital on Tuesday (Oct 21), a day after millions celebrated the Hindu festival of Diwali with fireworks that sent air pollution levels soaring to hazardous levels across the city.