Delhi air improves but smog still choking residents

STORY: Residents who stepped out for physical fitness were forced to jog and exercise in the thick haze as the air quality index (AQI) topped the 300-mark in most districts of the capital territory. Saturday's index was above 400.

Authorities in New Delhi ordered primary schools to shut from Saturday, and told schools to stop outdoor activities for older children, as air in the world's most polluted capital had become a severe risk to health.

According to data compiled by the Swiss group IQAir, New Delhi has been the world's most polluted capital for the past four years.