More than 7,000 buses, most of them from neighbouring states, were booked for flouting pollution norms in the national Capital in the last six years, Delhi Transport Minister Kailash Gahlot told the Assembly on Friday.

The minister said that 7,219 buses – 3,328 from Uttar Pradesh and 2,064 from Rajasthan – were booked between 2012 and February 2018 for not having valid pollution-under-check certificates. However, most of these bookings occurred in the last one year, with 5,086 buses getting penalised, PTI reported. The penalty for not having valid certificates is Rs 1,000.

The Delhi Transport Authority does not have the power to cancel the permits of buses from other states that violate pollution control norms in the city. If the buses belong to government-run agencies of other states, the transport department coordinates with these agencies, Gahlot added.

The city experienced hazardous levels of pollution in November and December 2017, which prompted Chief Minister Arvind Kejriwal to call the city a “gas chamber”.