CHENNAI: Within a few days after the Lok Sabha and Assembly by-elections were held in the State, the National Highways Authority of India (NHAI) has begun to implement revised toll fee rules, withdrawing the concession for locally registered commercial vehicles in toll gates across the State. While the top officials of NHAI claimed that the revised rules came into effect from April 1, the toll plazas across the State started to collect the same from the user for local commercial vehicles for the past few days, which so far enjoyed the 50 per cent concession on the user fee. A vehicle registered within a 20 km radius from the location of toll gate, is considered ‘local vehicle’.