New Delhi woke Monday to thick smog after Diwali firecrackers on Sunday, with air quality in several parts of the capital in the severe range, Al Jazeera and Deutsche Welle reported^1,2.

Al Jazeera said the Air Quality Index exceeded 350 in several neighborhoods Monday morning, a level it described as severe against World Health Organization exposure thresholds¹. DW said several parts of Delhi and surrounding satellite cities in the National Capital Region also logged severe-category readings and that haze cut visibility over roads and high-rises².

Residents set off firecrackers throughout Sunday evening despite restrictions, both accounts said^1,2. India's Supreme Court last month limited conventional firecrackers and allowed only approved green firecrackers in three-hour windows on Saturday and Sunday, Al Jazeera reported; those products still emit particulate matter¹. DW said the court limits did not hold in practice and that green crackers still emit 65 to 70 percent of the pollution from conventional ones².

DW, citing IQAir data from a government monitoring station as reported by AFP, said PM2.5 at Mandir Marg in central Delhi reached 879 micrograms per cubic meter early Monday, nearly 59 times the WHO daily guideline of 15 micrograms². Al Jazeera did not publish that station reading; it said pollution days before Diwali had already surged to more than 30 times the WHO daily limit¹.

The metropolitan region of about 30 million people often ranks among the world's most polluted capitals in winter, both reports said, when cooler, still air traps emissions^1,2. Al Jazeera cited India's environment ministry as attributing 23 percent of winter pollution to vehicles and 20 percent to biomass burning, including farm stubble fires¹. DW named vehicular emissions, crop-residue fires in neighboring states and industry as the recurring mix².

DW said winter pollution rules in New Delhi took effect Nov. 1, including vehicle restrictions and construction bans, and that Saturday had the worst Diwali-eve air in a decade². Al Jazeera noted haze can linger for days when winds are weak¹. Independent confirmation of the Mandir Marg figure beyond the IQAir/AFP citation in DW was not in this coverage².