New Delhi: North India is reeling under a wave of severe air pollution accompanied with smog as at least 12 cities on Thursday recorded an air quality index (AQI) of 400 and above, falling in the severe category.

With air pollution levels becoming uncomfortable in northern India, Ghaziabad is the most polluted city on Thursday with an air quality index (AQI) of 482 falling in the "severe" category.

As per AQI data from the Central Pollution Control Board (CPCB), among the cities with severe category pollution include Greater Noida at AQI count of 473, Hapur (477), Kaithal (463), Meerut (459), Bulandshahr (453), Noida (452), Kanpur (432), Kurukshetra (418), and Delhi (410).

Vivek Chattopadhyaya, Programme Manager, Air Pollution Control Unit, Centre for Science and Environment (CSE), said that the region adjoining Noida and Ghaziabad is witnessing very high AQI because of industrial pollution and waste burning.

He said that the adjoining areas of these cities are flanked by industrial clusters and combined with air pollution due to the trucks plying on NH 24 highway is also adding to the toxic levels of air pollution. The paucity of public transport is also causing high pollution in these cities.