India, Dec. 20 -- Traffic police have imposed checkpoints at four border crossings shared with Delhi on Friday to prevent the entry of vehicles into the national capital other than BS-VI and BS-IV petrol vehicles under the Graded Response Action Plan (Grap)-4, officials said.

At least 500 vehicles with inferior emission standards, including end-of-life vehicles (ELVs), were prevented from entering Delhi and diverted back to Gurugram at checkposts on the Delhi-Jaipur-Gurugram (NH 48), Dwarka Expressway, Aya Nagar village border in southwest, and Dhundahera-Kapashera border, said officials.

Deputy commissioner of police (DCP) (traffic) Dr Rajesh Mohan said the automatic number plate registration (ANPR) cameras on NH48 and Dwarka Expresswa...