Kathmandu, April 3 -- The Kathmandu Metropolitan City (KMC) has resumed random emission testing of vehicles since Wednesday, and early results show that around 75 percent of diesel-fuelled vehicles-buses, micro-buses and pick-up trucks-are emitting black smoke beyond permissible levels.

According to KMC's Environment Department, of the 42 diesel vehicles on which random testing was carried out on Friday, 31 failed. This is over 75 percent. On Thursday, testing was carried out on 26 vehicles and of them, 18 failed. So far, testing has been carried out on 100 petrol vehicles, and only seven failed, meaning that 93 percent petrol vehicles meet the emission standards set by the government.

"The problem is not much with petrol vehicles. Dies...