Indian schoolchildren cover their faces as they walk to school amid heavy smog in New Delhi on November 8, 2017. Delhi shut all primary schools on November 8 as pollution levels hit nearly 30 times the World Health Organization safe level, prompting doctors in the Indian capital to warn of a public health emergency. Dense grey smog shrouded the roads of the world's most polluted capital, where many pedestrians and bikers wore masks or covered their mouths with handkerchiefs and scarves. / AFP PHOTO / SAJJAD HUSSAIN
