NEW DELHI, Dec. 25 (Xinhua) -- As many as 45 flights were delayed at Delhi's international airport amidst dense foggy conditions and high air pollution levels on Tuesday.

The entire north India, including the states of Delhi, Haryana, Rajasthan, Punjab, Himachal Pradesh, Uttar Pradesh and parts of Madhya Pradesh have been witnessing dense fog over the past few days, particularly during morning and evening hours.

The situation is worsened due to high levels of air pollution. The air quality in Delhi and surrounding areas remained in the "severe" level for the fourth consecutive day on Tuesday as high humidity, low wind speed and cold weather are preventing the dispersal of particulates, said local media reports.

According to data from the Central Pollution Control Board (CPCB), the overall air quality index (AQI) in the Indian capital stood at 431.

Due to dense fog and high air pollution, visibility dropped to less than 50 meters in Delhi, thus delaying flights.

Only yesterday, as many as eight persons, including seven women, died in a massive pile up of as many as 50 vehicles in northern state of Haryana.