Following a tip-off that transporters were taking their vehicles to Nagaland to change the engine chassis number and fraudulently register their vehicles with the state authority.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/police-crack-down-diesel-vehicles-older-10-yrs-get-around-ngt-order-trucks-head-nagaland
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/indian-express-new-delhi
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/delhi
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/air-pollution
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/vehicular-pollution
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/diesel
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/national-green-trbunal-ngt
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/heavy-duty-vehicle