New Delhi, Dec. 17 -- The national capital, Delhi, witnessed a slight improvement in air quality on Wednesday morning, with the overall Air Quality Index (AQI) recorded at 328 at around 8 am, keeping it in the 'very poor' category, according to data from the Central Pollution Control Board (CPCB).

The air quality improved slightly compared to Tuesday, as the AQI was 354 at 4 pm. However, large parts of the city remained enveloped in toxic smog, and the overall air quality continues to be poor.

Anand Vihar was shrouded in thick smog, with an AQI of 341, placing it in the 'very poor' category. A thick layer of smog also engulfed areas around IGI Airport, ITO, Dhaula Kuan, AIIMS and the Ghazipur National Highway 24.

According to CPCB data...