Delhi's air quality back to 'severe', AQI in some areas nears 450

After improving to 'very poor' category on Saturday, Delhi's air quality index (AQI) has again deteriorated to 'severe' on Sunday amid the cold wave. The AQI in the national capital was recorded at 427 at 7 am. The AQI at Jahangirpuri stood at 441, Wazirpur at 434, Bawana at 432, Nehru Nagar at 430 and Anand Vihar at 427.