Delhi schools to close for a week due to smog

Levels of PM 2.5 particulates hit 20 times safe levels as agricultural fires add to city's air pollution crisis

Authorities in Delhi have announced that schools are to close for a week as the Indian capital's pollution control body warned of a looming health emergency due to smog.

Delhi is ranked one of the world's most-polluted cities, with a hazardous mix of factory and vehicle emissions and smoke from agricultural fires turning its air a toxic grey every winter.