Air quality in New Delhi deteriorated alarmingly on Diwali night as pollution levels spiked as much as 42 times higher than the normal in one of the most polluted spots of the capital, Hindustan Times reported.

At 10.55pm, PM10 was recorded at 4,273 µg/m³. PM2.5 also touched an alarming high at 748µg/m³ at 2.30am here. The permissible level of PM 2.5 is 60µg/m³ while PM10 is 100 µg/m³.

In general, Air Quality Index (AQI) showed that the air quality index had peaked -- touching the maximum limit of 500 -- in almost all monitoring spots in the city as fireworks induced smoke as part of Diwali festivities blanketed the city.

Daily air pollution level begins to grow in the capital of India from six in the evening, reaches peak at around eleven and remains high till six in the morning next day.

According to experts, the high content of suspended particles in air is extremely dangerous for people with asthma and heart disorders, as well as for children and elderly people.