India, Dec. 14 -- Delhi was shrouded in a thick haze on Sunday morning as air quality across the national capital slipped further into the 'severe' category.

According to data from the Central Pollution Control Board (CPCB), the Air Quality Index (AQI) stood at 462 at 6 am, reflecting extremely hazardous pollution levels.

All 40 air quality monitoring stations in the city reported 'red' readings, signalling severe air pollution. Rohini in northwest Delhi recorded an AQI of 499, the highest in the city, while Jahangirpuri and Vivek Vihar followed closely with AQI levels of 495.

The AQI is a public health indicator used to convey air pollution levels and their associated health risks.

It is calculated using eight key pollutants - PM10, ...