In several areas of the city, pollution levels were more than 50 times higher than the World Health Organization’s recommended safe limit. Forecasts say the poor air quality will continue into the week.

India's capital city of Delhi has virtually shut down as air pollution hit "severe plus" levels, according to Indian government officials in its pollution control authority.

A thick, toxic smog has enveloped India's capital, home to more than 33 million people. One technology firm which monitors air pollution ranked New Delhi as the most polluted city in the world.

Air pollution chokes New Delhi every winter, but this year's smog has already derailed everything from transport and road work to schools.

India's capital New Delhi switched schools to online classes Monday until further notice as worsening toxic smog surged past 60 times the World Health Organization's recommended daily maximum.- 'Stay indoors' - Primary schools were ordered to cease in-person classes on Thursday,

India's capital New Delhi switched schools to online classes Monday until further notice as worsening toxic smog surged past 60 times the World Health Organization's recommended daily maximum. Various piecemeal government initiatives have failed to measurably address the problem,