The Delhi government on Monday demanded that the Centre sponsor a new study to investigate the sources of particulate emissions in the national capital. Delhi Environment Minister Imran Hussain has written to his Union counterpart, Anil Dave, asking him to direct the Central Pollution Control Board to conduct the study, PTI reported.

The Aam Aadmi Party administration’s demand came even as the National Green Tribunal criticised it, along with the governments of Punjab, Haryana and Rajasthan, for the rise in pollution levels in the region. “What have you done till now to curb pollution?” the green panel asked. The NGT also inquired about the measures being taken against those violating the panel’s order on crop burning. “As much as 70% land in Punjab is used for crop burning. What is the Delhi government doing?” it said.

The tribunal had also suggested steps such as sprinkling water on roads and identifying alternatives to cremating corpses to curb pollution, according to PTI.

Moreover, Delhi Lieutenant Governor Najeeb Jung has directed authorities to ensure that measures to mitigate pollution levels are implemented immediately, ANI reported. He has also asked the Delhi Police and municipalities to start de-registering diesel trucks older than 15 years, in addition to issuing a ban on bursting crackers during occasions other than religious festivals. This followed a meeting with Chief Minister Arvind Kejriwal and other state ministers on the matter.

Furthermore, members of the Youth Congress protested outside Kejriwal’s house against the alarming rise in pollution in the Capital, while the Delhi Metro suspended all excavation, filling and concrete dismantling works taking into account the levels of smog in the city, ANI reported. On Tuesday, the Supreme Court will consider whether its orders on tackling environmental hazards in Delhi were consistently ignored by various authorities, according to NDTV.

The air quality in the National Capital Region has dropped significantly since the city celebrated Diwali on October 30 – made worse by cooler temperatures and lack of winds, which causes a harmful mix of respirable pollutants and toxic gases to remain close to the surface. The Centre for Science and Environment had said that Delhi has not been affected by such levels of smog in the last 17 years.