Hours after tens of thousands of people celebrated the Hindu Festival of Lights in News Delhi on Wednesday, a plume of toxic smog shrouded the city, turning day into dusk.
Smog had been increasing in recent day, and schools have been closed for three days and all kinds of construction work has been ordered to halt, but Diwali fireworks added to the pollution.
Harmful pollutants reached levels more than 20 times the safe limit in the Indian capital.
The World Health Organisation warned the smog could seriously aggravate heart or lung diseases.
The government blamed the toxic stew on a combination of the burning of stubble in agricultural fields and firecrackers.
It comes after revellers defied a Supreme Court order, which restricted the time firecrackers could be released to between 8pm and 10pm on the day of the festival.
Officials also banned diesel-run trucks from entering the city until the end of the week in order to control the pollution levels.
Rias Ahmed, an auto rickshaw driver, said it was highly unlikely that air pollution was going to decrease in and around the Indian capital.
“I have been driving an auto rickshaw since 1994, for 24 or 25 years, and it has been very difficult due to the high pollution.
"Sometimes when we clean our nose, it’s all black.
"When we spit or cough, that’s all black.
"This is a problem,” he said.
Authorities this week tried to reduce dust by sprinkling water in many neighborhoods and ordering builders to cover construction sites.
Coal-based power stations in the Indian capital region were also shut down.
The transport department was checking buses entering the region for valid emission papers and threatening to punish violators.