Shimla, July 30 (IANS): The National Green Tribunal (NGT) has asked the Himachal Pradesh government to explore the possibility of introducing compressed natural gas (CNG) vehicles in the state capital.

"The state government shall put forward its stand as to why traffic is being permitted on every road in Shimla, resulting in air and noise pollution," the NGT bench, comprising chairman Justice Swatanter Kumar and Justice U.D. Salvi, observed in its order Monday.

It asked: "Why all vehicles or even limited number of vehicles are being allowed to ply on each and every road right up to the telegraph office (located on the Ridge) on the one hand and the Regal building on the other?

"If at all, traffic is to be permitted on other roads leading up to the restricted areas, introduction of CNG vehicles may be explored."

A circuit bench of the NGT's principal bench, which held hearing in the Himachal Pradesh High Court here for two days from Monday, said: "Why due notification, covering all hospitals, schools, universities, dispensaries, institutional areas, etc. situated in the entire state as silent zones specifying that no noise or air pollution should be caused, particularly within 100 m of such institutional areas, is not being issued?"

Listing the matter for next hearing Sep 17, the NGT directed the state pollution control board to take ambient air quality samples from several intersection points in Shimla and submit a report.

Shimla has several auto-free zones to facilitate unrestricted movement of pedestrians.

The Mall and the historic Ridge, an open space just above the Mall which were once 'British only' streets meant for strolling, are among the auto-free zones.