Lucknow, Nov 15 : The ban on firecrackers in 13 Uttar Pradesh cities proved ineffectiveas people burst crackers with a vengeance on Diwali night. The air quality index in Lucknow zoomed to 881 by midnight and settled at 427 on Sunday morning. In Rajajipuram locality, the AQI was 752 on Sunday morning and Naka Hind, Qaiserbagh and Lalbagh areas recorded AQI at 450 -- all in the 'hazardous' category. Most people refrained from bursting crackers till about 8 p.m. when police vans were seen patrolling the various areas. However, after 9 p.m., people went berserk bursting firecrackers, even the high decibel ones. Rakesh Khatri, a businessman here, who burst a Rs 10,000 firecracker, explained, "I had bought these crackers much before the ban was announced. Storing the crackers can be dangerous because we have children in the house so I had to use them. When my neighbours starting bursting crackers after the Diwali puja, I also followed suit." Reports of firecrackers being used despite the ban are also came in from cities like Kanpur where AQI was 750 on Sunday morning. Other cities that defied the ban include Meerut, Moradabad and several other cities in western districts. A senior police official said that the administration has taken note of people defying the ban and necessary action would be taken against those responsible. /IANS