The Indian capital of New Delhi has been covered in thick smog and air pollution, prompting the government to issue more than five million masks to schoolchildren.

Video filmed on October 31 shows the depth of pollution in the skies, following the massive Hindu festival of Diwali on October 27.

Reportedly New Delhi's Air Quality Index has exceeded 500 AQI since October 28, with readings above 50 considered unsafe.

Contributing factors have included rural crop burning from nearby regions, industrial emissions and the city's over 10 million vehicles.

India's capital is choking on a thick, brown smog. New Delhi's Air Quality Index has exceeded 500 AQI for at least three days now. Readings above 50 are considered unsafe. Crop burning in neighboring regions send already bad pollution levels soaring in October and November. Farmers set their fields on fire to clear them of stubble from the just completed harvest. Emissions from power plants, industrial facilities, and the Delhi region's more than 10 million vehicles add to the toxic mix. Diwali - the Hindu festival of lights - is often seen as the unofficial start of air pollution season in India. The holiday was celebrated this year on October 27 with customary fireworks.