New Delhi, Nov. 5 -- A thick haze covered the city on Thursday as the air quality index (AQI) remained in the "very poor" category for the fourth consecutive day, just days ahead of Diwali as forecast said of a likely deterioration to "severe" levels from Friday

The 24-hour average stood at 369 on Thursday, according to the Central Pollution Control Board (CPCB)'s 4pm bulletin, just 8 points lower than Wednesday's 377. It was higher than 350 on Tuesday and 324 on Monday.

The CPCB classifies an AQI between 0 and 50 as 'good', 51-100 as 'satisfactory', 101-200 as 'moderate', 201-300 as 'poor', 301-400 as 'very poor' and 401-500 as 'severe'.

The Air Quality Early Warning System (AQEWS) has forecast that Delhi's air quality will remain "ve...