New Delhi, Oct. 17 -- The Supreme Court on Friday named retired Justice Madan B. Lokur as a one-man committee to monitor how Punjab, Haryana, Uttar Pradesh and Delhi NCR are implementing the ban on burning stubble after harvest.

An apex court bench headed by Chief Justice S.A. Bobde passed the order while hearing a public interest litigation filed by two environmental activists seeking directions to ensure that the ban is implemented in the northern states.

Senior advocate Vikas Singh, who represented the petitioners, said instances of stubble burning are up fivefold this year and suggested a retired apex court judge head a committee to monitor the preventive measures.

The bench, also comprising Justices A.S. Bopanna and V. Ramasubrama...